Pronunciation: [fɪftˈiːn] (IPA) 
The word "fifteen" is spelled with the letters F-I-F-T-E-E-N. In IPA phonetic transcription, it is represented as /ˈfɪf.tiːn/. The first syllable is pronounced as if it were spelled "fiff", with the /f/ sound followed by the short vowel /ɪ/. The second syllable, "-teen", is pronounced with the long vowel /iː/ and a nasal consonant /n/ at the end. Together, these sounds create the word "fifteen", which represents the number 15.
Fifteen is a cardinal number that represents the quantity or count of objects or entities that is equivalent to the sum of ten and five. It falls between the numbers fourteen and sixteen in the number line. In numerical form, fifteen is commonly represented as 15.
Fifteen can also be used as a noun to indicate a group of fifteen individuals or things. For instance, "There were fifteen guests attending the party."
Furthermore, "fifteen" can function as an adjective describing the characteristic of being equal to the number obtained by adding ten and five. For example, "She purchased fifteen apples from the market."
In terms of time, "fifteen" can refer to 15 minutes past the hour, particularly when indicating time on the analog clock. For example, "It is fifteen minutes after ten" denotes that the time is 10:15.
In sports, "fifteen" can be used to describe scoring points in rugby or American football. A team can achieve "fifteen points" by scoring either a try (equal to five points) or a try accompanied by a successful kick (worth seven points) or a drop goal (worth three points).
Overall, "fifteen" serves as a numerical value, noun, adjective, and even relates to specific time or scoring system in various contexts.
Five and ten.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
* The statistics data for these misspellings percentages are collected from over 15,411,110 spell check sessions on www.spellchecker.net from Jan 2010 - Jun 2012.
The word "fifteen" can be traced back to the Old English word "fīftēne", which was a combination of "fīf" meaning "five" and "-tēne" used to indicate the number (similar to the suffix "-teen" in modern English). This formation is also seen in words like "thirteen" and "fourteen". The Old English word evolved from Proto-Germanic language, where "fimf" meant "five". The origin of "fimf" can be traced back to the Proto-Indo-European root "*penkwe", which also meant "five". This root word has cognates in various Indo-European languages, such as "quinque" in Latin and "pente" in Greek, ultimately reflecting the ancient common ancestry of these languages.
