adverb
for whom
Archaic literary expression meaning 'for whom'. In modern Japanese, it is mostly encountered in titles, poetry, or fixed phrases, such as the famous novel title 誰がために鐘は鳴る (For Whom the Bell Tolls).
「誰がために鐘は鳴る」はヘミングウェイの小説の題名だ。
'For Whom the Bell Tolls' is the title of a Hemingway novel.
この歌は、誰がために歌われているのだろうか。
For whom is this song being sung, I wonder?
Modern standard expression for 'for whom'. 誰がために is archaic and literary.
Classical Japanese construction: 誰 (who) + が (possessive/archaic subject particle) + 為 (ため, sake/benefit) + に (particle). The が here is an archaic possessive or subject marker, not the modern conjunctive particle.