Rare spelling of 抗原 (“antigen”).

(host industry) Short for 元担当 (moto-tantō).

(uncommon) a commoner, an ordinary person (in contrast to the aristocracy or nobility)

(informal) ex-girlfriend

ex-boyfriend or ex-girlfriend

failure is a stepping stone to success

(mahjong) little three dragons: a 役 (yaku, “hand”) with triplets or quads of two of the 三元牌 (sangenpai, “dragon tiles”), plus a pair of the third; worth 2 翻 (han, “doubles”). Because 2 翻 is added from the 役牌 (yakuhai, “meld of seat/prevailing wind or dragon”) of the two dragons, the total is actually 4 翻.

(mahjong) Generic name of the three dragon tiles: 白 (haku, “white dragon”), 發/𤼵 (hatsu, “green dragon”), and 中 (chun, “red dragon”)

(mahjong) big three dragons: a 役満 (yakuman, “limit”) hand with triplets or quads of each of the 三元牌 (sangenpai, “dragon tiles”)

(monarchy) an East Asian practice of dating, using exactly one distinct era name for each monarch's reign, where such era name also eventually becomes the monarch's posthumous name