a particular kind of FUCKED PRONUNCIATION. Jukugo which don’t have okurigana generally use the ON-yomi. But KUNKUN words use the KUN yomi anyway, in defiance of the rules. For example:
靴下 (kutsushita – socks), 下着 (shitagi – underwears), and 悪口 (waruguchi – to badmouth someone)
Words with OKURIGANA are almost always KUNKUN anyway, so I don’t bother putting this tag on them.