a male cat; a tomcat.-to act like a cat.-a piece or slip of metal or wood, notched or otherwise, in a machine or structure, to hold other parts in place or bind them together, or to afford a bearing surface; -- usually held or adjusted by means of a wedge, key, or screw.-to secure or fasten with a gib, or gibs; to provide with a gib, or gibs.-to balk. see jib, v. i.