Definition - The phenomenon of sounds, such as consonant clusters, suggesting a particular meaning.

Example -
The sl in words like sleaze, slide, slime, slip, sludge, and slurry suggests slipperiness and sliminess.

Etymology -
The term derives from the Greek phone, voice or sound, and aisthesis, feeling or perception. It was probably coined by British linguist J. R. Firth who also coined the term phonesthemes.

Oxford English Dictionary -
Its first citation is from 1950:
"Phonaesthesia or sound symbolism."
(Archivum Linguisticum II. 97 )

Example Usages -

1. "The idea of "phonetic symbolism" — specifically a link between sounds and perception of size — appeared to me for the first time in Steven Pinker's Language Instinct. Some vowels are "high" in phonetic terminology, like [i] (as in "sweet"). Others are "low" (like [o]).

High vowels (with the tongue raised in the mouth) are often associated with small or delicate things, low vowels (where the oral cavity is made larger) with big things. In addition, "front" vowels, like [i] again, are seen as smaller than "back" vowels, like [u], which has the same height. As Mr Pinker put it, mice are teeny and squeak, elephants are humongous and roar."
(Source: Economist, When your tongue tricks your brain, Oct 26, 2010 )

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