Abbreviation of first. Assyrian Neo-Aramaic: ܐ. Danish: 1. Finnish: 1. Norwegian: 1. In summary, “1st” is correct, and “1th” is an error—but don’t let that scare you! English can seem complicated with its rules and exceptions, but with regular practice and a good attitude, you’ll get the hang of it. Define 1st. 1st synonyms, 1st pronunciation, 1st translation, English dictionary definition of 1st. Adj. 1. 1st - indicating the beginning unit in a series first ordinal - being or denoting a numerical order in a series; ordinal numbers ; held an ordinal. Ordinal numbers may be written in English with numerals and letter suffixes: 1st, 2nd or 2d, 3rd or 3d, 4th, 11th, 21st, 101st, 477th, etc., with the suffix acting as an ordinal indicator. First most commonly refers to: First or 1st may also refer to: Search for First or 1st on Wikipedia. La 1ère (disambiguation) (French: La Première, lit. 'The First') This disambiguation page lists articles associated with the title First. Quick Answer The most widely preferred and accepted way to write “first” in ordinal numerals is 1st. Using the numeric 1 followed by the two-letter suffix “st” (as in 1st, 2nd, 3rd, etc.) is the standard way to convey “first” in ordinal numbers in modern English. /fəst/ IPA guide Other forms: 1stly Definitions of 1st adjective indicating the beginning unit in a series synonyms: first Here is the short answer, in case you are in a rush: '1st' is the correct numeric abbreviation of the ordinal first. '1th' is a grammatical error, and it should never be used. The brief overview will help you if you need to quickly decide which spelling to use, but there is more to learn. Learn how to use ordinal numbers in English with clear grammar rules, common usage, and examples. Includes a full list from 1st to 100th. In this lesson, we're looking at the spelling of ordinal numbers and a few rules. 1st = first (She won first prize.) 2nd = second (I live on the 2nd floor.) 3rd = third (Take the third turning on the left.) 4th = fourth (It's his fourth birthday.) 5th = fifth (This is the 5th time I've taken my driving test.).