Definition of actin
: a cellular protein found especially in microfilaments (such as those comprising myofibrils) and active in muscular contraction, cellular movement, and maintenance of cell shape
Recent Examples of actin from the Web
The Senate could go to court, or go ask the Justice Department to go to court to enforce it, but either actin would require the Republicans who control the chamber to agree.
Like a pasta maker, the scale cell squeezes out and assembles a lattice of actins.
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Origin and Etymology of actin
International Scientific Vocabulary, from Latin actus
First Known Use: 1942See Words from the same year
Definition of actin-
1 : having a radiate form actinolite
2 : actinic radiation (such as X-rays) actinometer
Origin and Etymology of actin-
New Latin, ray, from Greek aktin-, aktino-, from aktin-, aktis; perhaps akin to Old English ūhte morning twilight, Latin noct-, nox night — more at night
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