(a nautical phrase). Inferior sailors, also called boys. A crew is divided into (1) Able seamen; (2) Ordinary seamen; and (3) Green hands or boys. The term “boys” has no reference to age, but merely skill and knowledge in seamanship. Here “green” means not ripe, not mature.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894