تضرّب

[He beat, struck, smote, or hit, himself much, or violently; or several, or many, times]. One says, تضرّب بِالحَصَى [He smote himself much with pebbles], (K in article كثح,) and بِالتُّرَابِ [with earth, or dust, as a man sometimes does in vexation]. (L ibid.)

See also 8, in two places.