A situation in which one player is checking his opponent continuously and his opponent is either unable or unwilling to evade the checks. Perpetual Check is not a rule of chess but will eventually lead to a draw by REPETITION.
Unremitting attack on a king, without checkmate. Under some rules this may result in a draw.
A situation where one player can give check to the enemy king indefinitely, resulting in a draw.
An infinite cycle in which one side gives check, the other side gets out of check, the first side checks again in the same way - being unable to do otherwise without risking the loss of the game - and so on. It constitutes a draw.
A draw forced by one player putting the opponent's king in a potentially endless series of checks.
In the game of chess, perpetual check is a special case of draw by threefold repetition, in which one player forces the repetition by an unending series of checks.