thirty-first: meaning, definition, pronunciation and examples
B1Neutral (used in formal, neutral, and informal contexts)
Quick answer
What does “thirty-first” mean?
The ordinal number corresponding to the cardinal number 31.
Audio
Pronunciation
Definition
Meaning and Definition
The ordinal number corresponding to the cardinal number 31; the position in a sequence after thirtieth.
The last day of January in the Gregorian calendar; also used metaphorically to denote the end of something or a concluding position.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Hyphenation standard in both varieties.
Connotations
Neutral in both varieties.
Frequency
Equally common in both varieties, primarily tied to calendrical references.
Grammar
How to Use “thirty-first” in a Sentence
the thirty-first of [Month/Year]on [the] thirty-firsther thirty-first [birthday/anniversary]Vocabulary
Collocations
Examples
Examples of “thirty-first” in a Sentence
adjective
British English
- We'll meet on the thirty-first day of the month.
- He celebrated his thirty-first birthday quietly.
American English
- The report is due on the thirty-first day.
- She won her thirty-first trophy this season.
Usage
Meaning in Context
Business
Used in deadlines and financial reporting periods (e.g., 'fiscal year ends on the thirty-first').
Academic
Used in historical dating and sequential numbering.
Everyday
Primarily for stating dates and birthdays.
Technical
Used in sequencing, indexing, and calendrical calculations.
Vocabulary
Synonyms of “thirty-first”
Neutral
Weak
Vocabulary
Antonyms of “thirty-first”
Watch out
Common Mistakes When Using “thirty-first”
- Writing as 'thirty first' without a hyphen
- Using cardinal 'thirty one' instead of ordinal 'thirty-first' (e.g., 'He came in thirty one' is incorrect).
FAQ
Frequently Asked Questions
Yes, ordinal numbers from twenty-first to ninety-ninth are consistently hyphenated in standard English.
You say 'thirty-first'. The 'st' from '1st' is added to the combined form.
Yes, e.g., 'We are meeting on the thirty-first.' Here it functions as a noun meaning 'the thirty-first day'.
'Thirty one' is the cardinal number (quantity). 'Thirty-first' is the ordinal number (position in a sequence).
The ordinal number corresponding to the cardinal number 31.
Thirty-first is usually neutral (used in formal, neutral, and informal contexts) in register.
Thirty-first: in British English it is pronounced /ˌθɜːti ˈfɜːst/, and in American English it is pronounced /ˌθɜːrṭi ˈfɜːrst/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “The thirty-first never comes (humorous, for months without 31 days)”
Learning
Memory Aids
Mnemonic
Think: 'Thirty' comes first, then 'first'—it's the first after thirty.
Conceptual Metaphor
TIME IS A SEQUENCE (position in a temporal or numerical order).
Practice
Quiz
Which of the following is the correct ordinal form for 31?