A connector includes a plurality of terminals, a housing, and a retainer. The housing includes terminal housing chambers and partition portions. Each of the terminal housing chambers accommodates therein each of the plurality of terminals. Each of the partition portions is provided between adjacent terminal housing chambers and partition the adjacent terminal housing chambers from each other. The retainer is attached to the housing. The retainer is configured to prevent each of the terminals from falling out and to move between a temporary locking position and a proper locking position. The retainer includes communication cut portions. While the retainer is moving between the proper locking position and the temporary locking position, each of the communication cut portions is kept in contact with its corresponding partition portion and cut off communication between the adjacent terminal housing chambers.