köken: Compound of 鶯(うぐいす) (uguisu, “Japanese bush warbler”) + 張(は)り (hari, “stretching”, 連(れん)用(よう)形(けい) (ren'yōkei, “stem or continuative form”) of the verb 張(は)る (haru, “to stretch”), rendaku form 張(ば)り (bari)), from the way that the floor creaks upon pressure.