a.

1. 松弛的，不紧的；不严的
2. 懈怠的；疏忽的；马虎的
3. 闲的，呆滞的，萧条的
4. （水流等）平缓的；迟钝的
5. 不坚定的，软弱的

vt.

1. 放松，使松弛
2. 减缓，使平缓
3. 马虎从事，松垮地做

vi.

1. 放松，变松弛[（+off/up）]
   It's natural to slack off towards the end of a hard day's work.

   一天紧张工作快结束的时候有些放松是自然的。

2. 减缓；减弱；变呆滞
3. 懒散；懈怠；马虎

n.

1. （绳索等的）松弛部分[U]
2. 松弛；懈怠；懒散[U]
3. （水流等的）迟缓；静止不动[U]
4. 淡季；萧条（期）[C][U]
   There's a certain amount of slack in the car industry at the moment.

   眼下汽车工业不太景气。

5. 宽松长裤；便裤[P]

ad.

1. 马虎地；松懈地
2. 缓慢地；没精打采地
3. 清淡地；呆滞地
4. 松弛地，宽松地

n.

1. 煤屑，煤末[U]

n.

1. 【英】峡谷；凹地；沼泽[C]

adj.

1. not taut or held tightly in position; loose.
2. (of business or trade) not busy; quiet.
3. careless, lazy, or negligent.
4. W. Indian lewd or promiscuous.
5. (of a tide) neither ebbing nor flowing.

n.

1. the part of a rope or line which is not held taut.
2. (slacks) casual trousers.
3. informal a period of inactivity or laziness.

v.

1. loosen (something, especially a rope).
2. (slack off/up) decrease in intensity or speed.
3. Brit. informal work slowly or lazily.
4. slake (lime).

n.