köken: Cognate with Kazakh жігерлі (jıgerlı, “active, vigorous”), Kyrgyz жигердүү (jigerdüü, “brave, valiant; active”). Ultimately derived from Persian جگر (jegar) in the sense of "spirit, courage".
köken: Appears to be root maji, which is cognate with まじまじ (majimaji, “staringly”), 瞬ぐ (majirogu, “to wink”) + 目 (me, “eye; visually prominent feature”), from the sense of eyes blinking nervously when having a straight face. First attested in the Nise Monogatari, around 1639–1640. The kanji spelling is an example of jukujikun (熟(じゅく)字(じ)訓(くん)) mixed with ateji (当(あ)て字(じ)), from 真 (ma-, “real”) + 面…
köken: Uncertain. Traditionally connected with dialectal ahku (“eagerness, zeal”), but this word is likewise of unknown origin. According to Häkkinen (2004), which follows Nikkilä (1998), perhaps a borrowing from dialectal Swedish ager (“hard-working”), but this sense for the word, supposedly found only in dialects within Finland, does not seem to have a particularly wide distribution nor even be the…