IPA: /ˈtɪə.ləs/
KK: /ˈtɪr.ləs/
Not producing or having tears.
She remained tearless during the sad movie.
Tearless → It is formed from "tear" (from Old English "tear", meaning a drop of clear salty liquid produced by glands in the eyes) and "-less" (meaning without). The word "tearless" means without tears or not producing tears.
Think of someone who is 'without' ('-less') 'tears' — that's why tearless means not shedding tears.