(intransitive) To gradually decrease in intensity or tautness; to become slack. / (transitive) To make slack, less taut, or less intense.

simple past tense and past participle of slacken

present participle of slacken

The act by which something slackens; loss of speed, tautness, etc.

Third-person singular simple present indicative form of slacken

One who slackens. / Part of a loom that slackens the threads.

plural of slackener

plural of slackening

(intransitive) To slacken or lessen; to become less intense. / (transitive) To do (something) less intensely.

(archaic) Third-person singular simple present indicative form of slacken