[Johnson (copied in later Dicts.) has the sense ‘The notch of an arrow,’ which he probably found in Ainsworth’s Thesaurus (1746–) ‘The cock of an arrow, Sagittæ crena.’ No evidence has been found for such a sense: it appears to be an etymological figment founded on Skinner’s conjecture that ‘cock of a gun’ (COCK sb.1 13) was a term originally proper to Archery, and identical with It. cocca ‘the nocke of an arrow’ (Florio).]
