adverb
even if; supposing that
Literary or formal concessive adverb, often used in hypothetical or resigned statements. Similar to たとえ～ても but more old-fashioned.
See also: 縦んば
よしや失敗しても、後悔はしない。
Even if I fail, I will have no regrets.
よしや彼が来なくとも、会議は予定
Even if he doesn't come, we will start the meeting as scheduled.