fatigue crack(n = noun.object) - a crack in metal resulting from metal fatigue;
is a kind of cleft, crack, crevice, fissure, scissure
battle fatigue, combat fatigue, crack, crack addict, crack down, crack down on, crack of doom, crack shot, crack up, crack willow, fatigue, fatigue duty, fatigue fracture, fatigue party, nasty crack, quarter crack, sand crack, take a crack at, toe crack