noun
sanity; soundness of mind; prudence
Almost exclusively used in the negative phrase たわいない (or たわいのない) meaning 'silly', 'trivial', or 'childish'. The standalone noun is rare.
See also: たわいない
彼の話はたわいがなかった。
His story was silly (lacked sense).
「たわい」という言葉は、ふつう「たわいない」の形で使わ
noun
Archaic meaning; not used in modern Japanese.
古語では「たわい」に酔いの意味があった。
In classical language, たわい had the meaning of drunkenness.
The word たわい is usually used in the form たわいない.
The common adjective meaning 'silly' or 'trivial', derived from たわい + ない. This is the usual way the concept is expressed.
The origin is uncertain. The kanji 他愛 is ateji (phonetic) and does not reflect the meaning. The word is now mostly fossilized in the negative form たわいない.