supplementary
gb/sˌʌpləmˈɛntɚi/ us/sˌʌpləmˈɛntɚi/
B2
English
~ 6900
Senses
0 senses
adjective
B2
property
1
additional; provided in addition
Added to something else to give more help, support, or information.
Usage pattern:
supplementary [noun]
Common mistake:
Learners often confuse "supplementary" with "complementary." "Supplementary" means something extra is added, usually in quantity or detail (supplementary income, supplementary information). "Complementary" means something different that fits well together or completes something in a matching way (complementary colors, complementary skills). Another common mistake is spelling it as "suplementary" (only one "p"); the correct spelling has double "p": "supplementary."
Synonyms
additional (Most common neutral alternative; almost always interchangeable in modern usage.)
|
extra (More informal and general; does not suggest an official or organized addition as strongly.)
|
supplemental (Very close in meaning; slightly more American and often used in technical, legal, or official contexts.)
|
ancillary (More formal; emphasizes a supporting role rather than just being added.)
Antonyms
main (Focuses on the primary or central part, which supplementary things are added to.)
|
primary (Stresses the first or most important part, as opposed to additional parts.)
Collocations
supplementary material
|supplementary information
|supplementary income
|supplementary insurance
|supplementary reading
|supplementary budget
Themes
education
|business
|law
|communication
|core_vocabulary
Examples
- The report includes supplementary material in the appendix for readers who want more detail.
- Students are given supplementary exercises to practice the grammar point.
- Many workers take on part-time jobs to earn supplementary income.
- The government announced a supplementary budget to cover the emergency costs.
- You can find supplementary information on our website after the webinar.
Learner examples
- The teacher gave us supplementary reading after class.
- He needs a supplementary job to pay his bills.
- Please see the supplementary file for more data.
- The company sent supplementary information by email.
- We did supplementary exercises for homework.
adjective
technical
B2
relation
2
angles adding up to 180°
Describes two angles whose sizes together make 180 degrees.
Usage pattern:
[two angles] are supplementary
Common mistake:
Learners often confuse "supplementary" and "complementary" in geometry. Remember: supplementary angles add up to 180° (a straight line), while complementary angles add up to 90° (a right angle).
Antonyms
complementary (angles) (In geometry, complementary angles add up to 90 degrees, while supplementary angles add up to 180 degrees.)
Collocations
supplementary angles
|pair of supplementary angles
|form supplementary angles
|are supplementary to
Themes
math
|education
|science
Examples
- If two angles form a straight line, they are supplementary angles.
- Angles A and B are supplementary because their measures add up to 180 degrees.
- In this diagram, angle x is supplementary to the 120-degree angle.
- The teacher asked us to find the measure of the angle supplementary to 45 degrees.
- Any two right angles are supplementary since they total 180 degrees.
Learner examples
- These two angles are supplementary because they make a straight line.
- Angle A is supplementary to angle B.
- Find the angle that is supplementary to 60 degrees.
- Two right angles are always supplementary.
- The book shows many pairs of supplementary angles.
Grammar
Dictionary form
supplementary
IPA
GB/sˌʌpləmˈɛntɚi/
US/sˌʌpləmˈɛntɚi/
Syllables & stress
sup - ple - ment - ary (4 syllables)
Stress on 3rd syllable (ment)
Word forms
Adjective
- Base: supplementary
Word family
Core family
supplement
noun B2
Related words
supplemental
adjective B2
Advanced or less common
supplementation
noun
Expressions
supplementary evidence
4/sˌʌpləmˈɛntɚi ˈɛvədəns/
fixed phrase
formal
additional proof or documents
Extra documents or other proof that are given to support a claim, story, or legal case.
Examples
- The lawyer submitted supplementary evidence before the final hearing.
- We may ask you for supplementary evidence of your identity.
supplementary income
3/sˌʌpləmˈɛntɚi ˈɪŋkˌʌm/
fixed phrase
extra money in addition to salary
Money you earn in addition to your main job or main source of money.
Examples
- She gives private English lessons to earn supplementary income.
- Many families depend on supplementary income from part-time work.
supplementary information
1/sˌʌpləmˈɛntɚi ˌɪnfɔɹmˈeɪʃən/
fixed phrase
extra facts or details
More facts or details that are given after or in addition to the main information.
Examples
- If you need supplementary information, please contact our support team.
- The witness later provided supplementary information that helped the investigation.
supplementary material
2/sˌʌpləmˈɛntɚi mətˈɪɹiəl/
fixed phrase
extra documents or content
Extra texts, files, or other content that are added to the main book, article, or presentation to give more information.
Examples
- The article includes supplementary material online, such as videos and raw data.
- Please check the supplementary material at the end of the book for practice tests.
supplementary reading
5/sˌʌpləmˈɛntɚi ɹˈidɪŋ/
fixed phrase
extra reading for a course
Books or articles that a teacher gives in addition to the main textbook, usually to help students learn more.
Examples
- The professor posted a list of supplementary reading on the course website.
- This article is supplementary reading for students who want to explore the topic further.