If something slackens or if you slacken it, it becomes slower, less active, or less intense.
例句
Inflationary pressures continued to slacken last month...上個月，通貨膨脹的壓力繼續減小。The Conservative government will not slacken the pace of radical reform.保守黨政府不會放慢激進改革的步伐。
V-ERG
(使)松開;(使)放松
If your grip or a part of your body slackens or if you slacken your grip, it becomes looser or more relaxed.
例句
Her grip slackened on Arnold's arm...她緊握著阿諾德的手松開了。Muscles stretch, slacken and relax during childbirth.生孩子的時候，肌肉會拉抻、放松，然后松弛下來。
英漢詞典釋義
vt. & vi.
(使)松弛
Slacken your legs and slowly lie back.放松雙腿, 慢慢向后躺下。
(使某物)放慢, 遲緩
Simon allowed his pace to slacken.西蒙放慢了腳步。
松懈下來；變遲緩
We’ve been really busy, but things are starting to slacken off now.我們忙極了，不過現在事情開始減少了。
英英詞典釋義
Verb
1. become slow or slower;
"Production slowed"
2. make less active or fast;
"He slackened his pace as he got tired""Don't relax your efforts now"