The name Crk is from "CT10 Regulator of Kinase" where CT10 is the avian virus from which was isolated a protein, lacking kinase domains, but capable of stimulating phosphorylation of tyrosines in cells.
Crk's name is rooted in its origin from the term "CT10 Regulator of Kinase," referring to an avian virus (CT10) that resulted in the identification of a protein lacking kinase functions but capable of initiating tyrosine phosphorylation in cell processes.