Lab (?), v. i. [Cf. OD. labben to babble.] To prate; to gossip; to babble; to blab. [Obs.] Chaucer.[1913 Webster]
lab, n. 1. A telltale; a prater; a blabber. [Obs.] “I am no lab.” Chaucer.[1913 Webster]
2. [By truncation of laboratory.] Laboratory. [Colloq.][PJC]
lab, a. Of or pertaining to a laboratory; as, a lab bench. [Colloq.][PJC]