noun
Rarely used alone; almost always appears in the negative expressions 他愛ない or 他愛もない, meaning 'trifling', 'silly', or 'unselfish' depending on context. The standalone noun sense 'altruism' is literary and uncommon.
「他愛」という言葉は、普通は「他愛ない」という形で使われる。
The word 他愛 is normally used in the form 他愛ない.
彼の行動には他愛が
There was altruism in his actions.
The origin is uncertain. 他愛 is a kanji compound literally meaning 'other love', but the word is almost exclusively used in the negative form 他愛ない, which may have developed from a different root. The exact derivation is unclear.