名詞 must:

1. a necessary or essential thing
2. grape juice before or during fermentation
3. the quality of smelling or tasting old or stale or mouldy
   同義詞：mustiness, moldiness

形容詞 must:

1. highly recommended

1. Something must be done about it.
   必須得想個辦法。
2. His new novel is a must for all lovers of crime fiction.
   他的新小說是罪案小說愛好者必須一讀的。
3. In England traffic must keep to the left.
   在英國，車輛必須靠左行駛。
4. Her beauty-salon was always full and she must have made a bomb thereby.
   她的美容院總是客滿，因此她一定掙了大筆的錢。
5. The girl was back in a pig's whisper. She must have run all the way.
   那個女孩一會兒就回來了。她肯定是跑著去跑著回的。

must

v.aux.（助動詞）
To be obliged or required by morality, law, or custom:
必須：為道德良心、法律或者習慣所要求或強迫：
例句：
Citizens must register in order to vote.
為了進行選舉，公民們必須登記

To be compelled, as by a physical necessity or requirement:
必須，必要：由于物質需要和要求而被迫：
例句：
Plants must have oxygen in order to live.
為了存活植物必須有氧氣

Used to express a command or an admonition:
一定，必須：用來表示命令或者愿望：
例句：
You must not go there alone. You simply must be careful.
你一定不要單獨去那里。你一定要小心

To be determined to; have as a fixed resolve:
一定：下決心一定要；堅持要：
例句：
If you must leave, do it quietly.
如果你一定要離開，那就悄悄地走

Used to indicate inevitability or certainty:
表示不可避免性或者可能性：
例句：
We all must die.
我們都會死

Used to indicate logical probability or presumptive certainty:
可能：用來表示邏輯推斷的可能性或假定的必然性：
例句：
If the lights were on, they must have been at home.
如果燈亮著，那么他們一定在家

v.intr.Archaic （不及物動詞）【古語】
To be required or obliged to go:
被要求或被迫去：
例句：
.I must from hence.(Shakespeare)
.我必須從這里走.(莎士比亞)

n.（名詞）
Something that is absolutely required or indispensable:
一定，絕對：絕對必要或不可避免的應當去做之事：
例句：
Promptness on the job is a must. Comfortable shoes are a must when taking a walking tour of Wales.
工作上準時是絕對必要的。步行去威爾士旅行時舒服的鞋是絕對必要的物品

n.attributive.（定語名詞）
Often used to modify another noun:
常用來修飾另一個名詞：
例句：
a new book that is must reading; a list of must legislation for the session.
一本不可不讀的新書；開庭不可缺少的立法一覽表

來源：
Middle English moste
中古英語 moste
from Old English môste [past tense of] môtan [to be allowed] * see med-
源自 古英語 môste [] môtan的過去時 [被允許] *參見 med-

must
must 2

n.（名詞）
The quality or condition of being stale or musty.
發(fā)霉：陳腐或者發(fā)霉的特性或狀態(tài)

來源：
Probably back-formation from musty
可能源自 musty的逆成詞

must
must 3

n.（名詞）
The unfermented or fermenting juice expressed from fruit, especially grapes.
果汁：從水果中壓出的發(fā)酵或者未發(fā)酵的果汁，特別是從葡萄中擠出的

來源：
Middle English
中古英語
from Old English
源自 古英語
from Latin mustum [neuter of] mustus [new, fresh]
源自 拉丁語 mustum [] mustus的中性 [新的，新鮮的]

must
must 4

n.（名詞）
Variant of musth
musth的變體

must
must 5

n.（名詞）
Musk.
麝香

來源：
Scottish
蘇格蘭語
from Old French
源自 古法語
variant of musc * see musk
musc的變體 *參見 musk