calmodulin
noun
cal·mod·u·lin (ˌ)kal-ˈmä-jə-lin 
-dyu̇-lin
: a calcium-binding protein that mediates cellular metabolic processes (such as the contraction of muscle fibers) by regulating the activity of calcium-dependent enzymes
Example Sentences
Recent Examples on the Web This seemed significant: Other calmodulin variants were associated with severe cardiac disorders and sudden death in infancy. 
Oscar Schwartz, Wired, 9 Dec. 2021 Cunningham and her postdoc at the time, Christine Kirvan, found that the antibodies literally bind to human neurons, activating an enzyme called calcium/calmodulin-dependent protein (CaM) kinase II. Pamela Weintraub, Discover Magazine, 29 Mar. 2017
Oscar Schwartz, Wired, 9 Dec. 2021 Cunningham and her postdoc at the time, Christine Kirvan, found that the antibodies literally bind to human neurons, activating an enzyme called calcium/calmodulin-dependent protein (CaM) kinase II. Pamela Weintraub, Discover Magazine, 29 Mar. 2017 Word History
Etymology
calcium + modulate + -in entry 1
First Known Use
1978, in the meaning defined above
Medical Definition
calmodulin
noun
cal·mod·u·lin ˌkal-ˈmäj-ə-lən
: a calcium-binding protein that mediates cellular metabolic processes (as muscle-fiber contraction) by regulating the activity of specific calcium-dependent enzymes