- must
- mustmust1 [must]v.aux.pt.must [ME moste, pt., had to < OE, pt. of motan, may, akin to Goth (ga)mot, (I) find room, am permitted, prob. < IE * mōt-, var. of * med-, to measure > METE1]1. used to express compulsion, obligation, requirement, or necessity [I know I must pay her; I knew I must pay her]2. used to express probability [then you must be my cousin; I thought he must be my cousin]3. used to express certainty or inevitability [all men must die; they knew they must die]: As a modal auxiliary, must is followed by an infinitive without tovi.used elliptically in the same functions as MUST1 (v.aux. ) [shoot if you must]n.Informalsomething that must be done, had, read, seen, etc. [this book is a must]adj.Informalthat must be done, etc.; necessary; essential [must reading]must2 [must]n.[Hindi mast, intoxicated < Pers mast < IE base * mad-, to be moist > MEAT]a state of frenzy in animals, esp. in the male elephant, usually associated with sexual heatadj.in mustmust3 [must]n.[ME < OE < L mustum, new wine, neut. of mustus, new, fresh < IE base * meu-, moist > MOSS]the juice pressed from grapes or other fruit before it has fermented; new winemust4 [must]n.[back-form. < MUSTY]a musty quality or state; mustiness
English World dictionary. V. Neufeldt. 2014.