Definition of actin
(Entry 1 of 2)
: a cellular protein found especially in microfilaments (such as those comprising myofibrils) and active in muscular contraction, cellular movement, and maintenance of cell shape
actin-
combining form
variants:
or actini-
or actino-
Definition of actin- (Entry 2 of 2)
1
: having a radiate form
actinolite
2
: actinic radiation (such as X-rays)
actinometer
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Merriam-Webster unabridged
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Time Traveler for actin
The first known use of actin was in 1942
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