|a verb used to indicate the tense, voice, mood, etc, of another verb where this is not indicated by inflection, such as English will in he will go, was in he was eating and he was eaten, do in I do like you, etc|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|a fool or simpleton; ninny.|
A “helping” verb that modifies the main verb, as in “Gail can win,” “Gail did win,” “Gail could have won.” A question often begins with an auxiliary verb: “Did Gail win?” “Could Gail lose?” The various forms of the verbs can, have, is, and does frequently act as auxiliaries.