quietude 靜
the state of being quiet; tranquillity; calmness; stillness; quiet
n. 寂靜; 平靜; 鎮靜; 沉著

inquietude
A state of restlessness or uneasiness; disquietude
n. 不安；焦慮

quietus
Something that serves to suppress, check, or eliminate.
Release from life; death.
A final discharge, as of a duty or debt.
n. 生命的終止；寂滅；解除；償清

quiescence
the quality or state of being quiescent
n. 靜止；沉默

disquiet
To deprive of peace or rest; trouble.
Absence of peace or rest; anxiety.
lack of calm, peace, or ease; anxiety; uneasiness.
vt. 使不安；使擔心，使憂慮
n. 擔心，不安；焦慮，憂慮

例句：
The President's speech caused considerable disquiet in some European capitals.
總統的演說在一些歐洲國家首都引起很大不安。

acquiesce ac- = ad-, to qui-quiet coalesce
To consent or comply passively or without protest.
vi. 默許；勉強同意

例句：
After a lot of persuasion,he finally acquiesced.
經過多次勸說，他最終默許了。

acquiescence
Passive assent or agreement without protest.
The state of being acquiescent.
n. 默許；默從

acquiescent
Disposed or willing to acquiesce.
adj. 默認的；默許的；甘心接受的

例句：
Far from being unctuous, Pat was always loath to appear acquiescent.
由于并不愿意假意奉承，所以帕特總是不愿意表現出勉強順從的姿態。