The spelling of "thirty first" is quite straightforward once the pronunciation is known. The word is pronounced /ˈθɜː.ti fɜːst/ in IPA phonetic transcription. The first syllable "thir" is pronounced with the voiced dental fricative /ð/, while the second syllable "ty" is pronounced with the alveolar tap /ɾ/. The final syllable "first" is pronounced with the voiced dental fricative /ð/ again and the voiceless dental fricative /θ/ at the beginning, resulting in a smooth flow from the "th" sound of "thirty" to the "f" sound of "first."
Thirty-first is an adjective that refers to the ordinal number corresponding to the quantity of 31 in counting order. It represents the position in a sequence, particularly in the order of numbers. The term "thirty-first" is derived from the cardinal number "thirty-one" by adding the suffix "-st" which indicates that it is an ordinal number.
When used in the context of dates, particularly referring to a specific day in a calendar month, "thirty-first" signifies the last day of the month. It holds significance as it concludes a month and often carries special characteristics or occurrences associated with the ending of a cycle.
In numerical equations or calculations, "thirty-first" is utilized to represent the numerical value of 31 in mathematical operations.
The term "thirty-first" is commonly used in everyday language to indicate the position of an item, event, or person in a sequential order. It can also be employed to explain the chronological order of actions or the arrangement of elements in a series. Additionally, "thirty-first" can be utilized to describe rankings or placements in competitions, contests, or races.
Overall, "thirty-first" is an adjective that serves as an identifier for the ordinal number 31, denoting its specific position in a series or sequence.
The etymology of the word thirty first is derived from the combination of two elements: thirty, which comes from the Old English word þritig meaning thirty, and first, which ultimately stems from the Old English word fyrst meaning first. These two terms are combined to denote the ordinal number thirty first.