The Prefix SUB- (32 Examples・Free 9-page PDF・Video)

Learning prefixes is an awesome way to increase your English vocabulary. This post will teach you how to use the prefix sub- with lots of real example sentences.

The prefix SUB- 

1. Below or less than

  • I live in a subtropical area.

2. Under

  • Let’s take the subway to save on parking.

3. A smaller part of something

  • Only a small subset of patients qualify for the drug trial.

Keep reading to learn some common words that use the prefix sub- and understand the meaning of the root words with their own dictionary definition links.

The Prefix SUB-

The prefix sub- has three meanings. 

#1. (in nouns and adjectives) below; less than
We are expecting heavy snow, strong winds, and sub-zero temperatures tomorrow.
[Temperatures below zero degrees.]

#2. (in nouns and adjectives) under
– If we take the subway we can save money on parking downtown. 
[Subways are trains that travel under the ground.]

#3. (in verbs and nouns) a smaller part of something
– They are building a new subdivision behind the school. 
[A subdivision is an area of land (a smaller part) that has been divided up for building houses on.]

sub- [prefix] 

Word Origin
from Latin sub ‘under, close to’.

For a word to be included in this post, the prefix sub- must be added to an already existing word to change the meaning. Words like subject and subvert did not qualify. (Ject and vert are not words.)

Adjectives with the prefix SUB-

subarctic – relating to the region just south of the Arctic Circle

  • Subarctic forests are at risk due to climate change. 

Root meaning arctic

subconscious – connected with feelings that influence your behavior even though you are not aware of them

  • Many commercials and advertisements try to affect your mind on a subconscious level. 

Root meaning conscious

suboptimal – of less than the best standard or quality

  • Military hospitals inside a warzone do the best they can in harsh conditions. The environment is suboptimal for healthcare. 

Root meaning optimal

subprime – connected with the practice of lending money to somebody who is likely to have difficulty paying it back

  • Dennis had a low-paying job so he applied for a subprime mortgage when he bought a house. 

Root meaning prime 

The Prefix sub- Subprime

sub-Saharan – from or relating to areas in Africa that are south of the Sahara Desert

  • Motorcycles have recently become quite popular in sub-Saharan Africa. There are more motorcycles on the road now than ever before. 

Root meaning Sahara

Did you know?
The Sahara desert is the largest hot desert in the world. Smaller only than the cold deserts of Antarctica and the northern Arctic. LINK

substandard – not as good as normal; not acceptable

  • After opening 3 cases, we discovered the products were substandard and immediately sent them back to the factory. 

Root meaning standard

subtropical – in or connected with regions that are near tropical parts of the world

  • Bananas grow well in subtropical climates. 

Root meaning tropical

suburban – in or connected with a suburb

  • I was lucky to be raised in a suburban environment. We were close enough to the city to enjoy the convenience but far enough away to not be bothered by large crowds, bright lights, and noise. 

Root meaning urban

sub-zero – below zero

  • We are expecting heavy snow, strong winds, and sub-zero temperatures tomorrow.

Root meaning zero

Did you know?
The Eastern Antarctic Plateau, Antarctica is the coldest place on Earth. Air temperatures can be around -94°C. LINK

Two adverbs with the prefix sub-

subconsciously adverb – as a result of feelings that influence your behavior even though you are not aware of them

  • Commercials try to subconsciously affect our shopping habits. Ad companies are very sneaky. 

suboptimally adverb – not in the best way; not to the highest standard

  • Ryan’s stomach cramps were caused by a suboptimally distended bladder.

*This adverb is quite rare.

FAQ – Difference between Urban and Rural

The root word of Suburban is Urban. Some of my private students have asked me to explain the difference between urban and rural. Here is what I teach them.

Urban vs Rural
(city vs countryside)

Urban is an adjective that means connected with a town or city

“I used to live in Tokyo. Tokyo is very big, with lots of people, buildings, and businesses. Tokyo is an urban area.”

urban Oxford Learner’s Dictionary HERE
Rural is an adjective that means connected with or like the countryside

“My family is from a very rural part of Ontario. The population is small, and there are few big buildings or businesses.”

rural Oxford Learner’s Dictionary HERE
Urban Vs Rural

Nouns with the prefix SUB-

subconscious – the part of your mind that contains feelings that you are not aware of

  • Advertisers are always trying to influence our subconscious.

Root meaning conscious

The Prefix sub- Subconscious

subcontractor – a person or company that does part of the work given to another person or company

  • The renovation company uses subcontractors to do the carpeting and painting. 

Root meaning contractor

subculture – the behavior and beliefs of a particular group of people in society that are different from those of most people

  • The police send undercover officers inside the city’s criminal subculture. It’s dangerous work but it’s necessary. 

Root meaning culture

subdivision – an area of land that has been divided up for building houses on

  • They are building a new subdivision behind the school. 

Root meaning division

subfloor – a rough floor laid as a base for a finished floor

  • The subcontractor needs 3 days to do the floors. The first day is to measure and build the subfloor and the next 2 days are for tile installation. 

Root meaning floor

The Prefix sub- Subfloor

subgenre – a genre that is part of a larger genre

Root meaning genre

subgroup – a smaller group made up of members of a larger group

  • The survey asked 3 questions from people across 18 subgroups divided by ideology, religiosity, and age.

Root meaning group

Do you know Reddit?

Reddit is a network of communities where people can read and write about their interests, hobbies, and passions. A subreddit is a Reddit community or group dedicated to one topic. (A subgroup)

subheading – a title given to any of the sections into which a longer piece of writing has been divided

  • A good blog post is divided into clear headings and subheadings. This makes the information easier to read and understand. 

Root meaning heading

Writing blog posts is what I do! Check out one of my most popular prefix posts here: The Prefix RE – 60 examples (Definitions, Free PDF, Video)

sublet – property and especially housing obtained by or available through a sublease

  • When I get to town I’m going to look for a sublet that I can stay in for a few weeks. A quiet place where I can finish writing my book. 

Root meaning let

submarine – a ship that can travel underwater

  • France has a deal to sell nuclear submarines to Australia. 

Root meaning marine

Submariner is the name of a high-quality diving watch made by Rolex. Diving watches are specially made to work underwater. (Just like a submarine.) Rolex

The Prefix sub- Submariner watch


Namor The Sub-Mariner is the name of a Marvel Comic character who lives underwater. Wiki
Did you know? The Submariner comic came before Aquaman? LINK

The Prefix sub- Namor the Submariner

This Photo by Unknown Author is licensed under CC BY-NC-ND

subplot – a series of events in a play, novel, etc. that is separate from but linked to the main story

  • I’m a big fan of this TV show, I like the characters and their subplots are always interesting. 

Root meaning plot

The Prefix sub- Subplot

subquery [computing] – A query embedded within a more extensive query, relating only to the data returned by the parent query.

  • The files I was looking for were located on a subquery on an external hard drive. 

Root meaning query

subset – a smaller group of people or things formed from the members of a larger group

  • Only a small subset of patients qualify for the drug trial.

Root meaning set

The Prefix sub- Subset

subtitles – words that translate what is said in a film into a different language and appear on the screen at the bottom

  • I like to watch foreign movies with subtitles.  

Root meaning title

The Prefix sub- Subtitles

subtotal – the total of a set of numbers which is then added to other totals to give a final number

  • I finally learned how to use the subtotal function in Microsoft Excel. 

Root meaning total

What Does Suburbs Mean?

Suburb is a noun that means an area where people live that is outside the center of a city.
We often talk about areas like using the plural form suburbs.

  • I liked growing up in the suburbs. I had many friends there’s always something fun to do. 
Prefix SUB- suburbs

Sub = below
Urb = urban (connected to a city)

Definition link for suburb
Definition link for urban

subway – an underground railway system in a city

  • I’ve lived in Japan for many years and I’m still surprised how the subways, trains, and buses are always on schedule. It’s amazing.

Root meaning way

subwoofer – a part of a loudspeaker that produces very low sounds

  • Lucas just bought some wireless subwoofers for his home theater system. They sound great. 

Root meaning woofer

The Prefix sub- Subwoofer

Verbs with the prefix SUB-

sublet – to rent to somebody else all or part of a property that you rent from the owner

  • I stay with my parents for a few months every summer. I sublet my apartment in the city during that time to make some extra money. 

Root meaning let   

subscribe – to arrange to have regular access to an electronic information service or other Internet services

  • I have subscribed to a YouTube channel and 3 subreddits about fishing. 

Root meaning scribe

subtitle – to give a subtitle or subtitles to a book, film, etc.

  • I have one client in Japan who subtitles western movies for the Japanese audience. I often consult with her on English movies and TV shows. 

Root meaning title

Do you watch English movies with subtitles? Do you study with English movies and TV shows? Check out my post: Learn English from TV – A complete guide (3 Tips)

Advanced Vocabulary 

I have included two more vocabulary words here that are a little bit advanced but I have heard them once or twice in movies or in conversation. 
Note that these two words are using the suffix sub- to mean below but they’re not connected to a root word that is used by itself.


A business or company that is owned or controlled by another, larger company is a subsidiary.

Google, Calico, and DeepMind are all subsidiaries of Alphabet Inc. They are companies owned by Alphabet.

More info about these companies from Wikipedia below:

Word Origin
mid 16th cent. (in the sense ‘serving to help or supplement’): from Latin subsidiarius, from subsidium ‘support, assistance’.


If something is located under the ground we can use the adjective subterranean.

  • Many historical buildings have private access to underground chambers. Guided tours through the subterranean city are a tourist highlight.

Word Origin
early 17th cent.: from Latin subterraneus (from sub- ‘below’ + terra ‘earth’) + -an.

Can you think of some prefix sub- words that I left out? Please tell me in the comments.

Prefix SUB- 9-page PDF

Download your printable 9-page PDF E-guide below. (It’s FREE!) The PDF contains the live links from the post.↓

Check out these other great Prefix and Suffix posts.

Discover more from World English Blog

Subscribe now to keep reading and get access to the full archive.

Continue reading

Scroll to Top