modal verb
Linguistics term for a verb that expresses modality, such as possibility, necessity, or obligation. In Japanese grammar, often refers to auxiliary verbs like れる/られる, せる/させる, たい, べき, etc.
Modal verbs express meanings such as possibility and obligation.
Japanese modal verbs are often treated as auxiliary verbs.
Compound of 法 (ほう, 'modality') and 動詞 (どうし, 'verb'), likely a calque from Western linguistic terminology.