Definition - The shortening of a syllable or vowel.

Example -
Wasamatta? (i.e. What's the matter?)

Etymology -
The word derives from the Greek systole, contraction (from syn, together, + stellein, to put).

Oxford English Dictionary -
Its first citation is from 1577:
"Systole, when a long Sillable is made shorte, contrary to the nature therof…."
(Henry Peacham, the Elder, The Garden of Eloquence (1577), Eijb)

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