P is the sixteenth letter

Letter (alphabet)

A letter is a grapheme in an alphabetic system of writing, such as the Greek alphabet and its descendants. Letters compose phonemes and each phoneme represents a phone in the spoken form of the language....

 of the basic modern Latin alphabet

Basic modern Latin alphabet

The International Organization for Standardization basic Latin alphabet consists of the following 26 letters:By the 1960s it became apparent to the computer and telecommunications industries in the First World that a non-proprietary method of encoding characters was needed...

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In English

English language

English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...

 and most other European languages, P is a voiceless bilabial plosive

Voiceless bilabial plosive

The voiceless bilabial plosive is a type of consonantal sound used in many spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is p...

. Both initial and final Ps can be combined with many other discrete consonant

Consonant

In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are , pronounced with the lips; , pronounced with the front of the tongue; , pronounced with the back of the tongue; , pronounced in the throat; and ,...

s in English words. A common example of assimilation

Assimilation (linguistics)

Assimilation is a common phonological process by which the sound of the ending of one word blends into the sound of the beginning of the following word. This occurs when the parts of the mouth and vocal cords start to form the beginning sounds of the next word before the last sound has been...

 is the tendency of prefixes ending in N to assume an M sound before Ps (such as in + pulse → impulse — see also List of Latin words with English derivatives).

A common digraph in English is ph, which represents the voiceless labiodental fricative

Voiceless labiodental fricative

The voiceless labiodental fricative is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is .-Features:Features of the voiceless labiodental fricative:...

 /f/, and can be used to transliterate Phi

Phi

Phi may refer to:In language:*Phi, the Greek letter Φ,φ, the symbol for voiceless bilabial fricativeIn mathematics:*The Golden ratio*Euler's totient function*A statistical measure of association reported with the chi-squared test...

 (φ) in loanwords from Greek

Greek language

Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

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