mass noun
- a substance that has no fixed shape and yields easily to external pressure; a gas or (especially) a liquid流体; 气体, 液体（尤指液体）：
drink a litre of fluid a day
每天喝一升流质
count noun a cleaning fluid.去污液。
1
- (of a substance) able to flow easily（物质）能流动的, 易流动的：
the paint is more fluid than tube watercolours
这种颜料比筒状水彩颜料更湿软
a fluid medium.
流动介质。
1.1
- not settled or stable; likely or able to change不固定的, 不稳定的, 易变的：
our plans are still fluid
我们的计划还没最后确定
the fluid political situation of the 1930s.
20世纪30年代不稳定的政治局势。
1.2
- smoothly elegant or graceful优美的, 流畅的：
her movements were fluid and beautiful to watch.
她的动作流畅优美。
1.3
- (of a clutch or coupling) using a liquid to transmit power（离合器, 联轴节）液压传动的, 液力传动的。
派生词
fluidity
nounfluidly
adverb词源
late Middle English (as an adjective)： from French fluide or Latin fluidus, from fluere 'to flow'.