noun
mishit; poor stroke; poor shot
Used in sports like baseball, tennis, or golf for a swing or hit that fails to connect properly, resulting in a weak or inaccurate shot.
バッターは打ち損ないのゴロを打った。
The batter hit a weak grounder off a mishit.
テニスで打ち損ないが多くて負けた。
I lost because of too many mishits in tennis.
空振り means a complete miss (swing and miss), while 打ち損ない implies contact was made but poorly.
凡打 is a routine, easily fielded batted ball in baseball; 打ち損ない emphasizes the failure of the swing itself.
Compound of 打ち (stem of 打つ 'to hit') + 損ない (stem of 損なう 'to fail, to make a mistake'). Literally 'hitting failure'.