ETYM AS. balca beam, ridge; akin to Icel. bâlkr partition, bjâlki beam, OS. balko, German balken; cf. Gael. balc ridge of earth between two furrows. Related to Balcony, Balk, Bulk.
(Baseball) An illegal pitching motion while runners are on base.

ETYM Prob. from Dutch balken to bray, bawl.
1. To stop at an obstacle and refuse to go on, usually out of fear.
2. (Baseball) To feign a pitch while runners are on base, usually in an attempt to draw a player off-base.