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general::
1. Also, take a hand in. Participate, be involved, as in I'd like to have a hand in planning the publicity. [Late 1500s] 2. have or keep one's hand in. Be actively engaged or remain in practice doing something. For example, He works as stage manager, director, understudy? he has a hand in every aspect, or Write a few pages every day, just to keep your hand in. [Mid-1700s]
American Heritage Idioms