1. (verb) become slow or slower

• slack
• slow
• slow down
• slow up

2. (verb) make less active or fast

• relax
• slack
• slack up

3. (verb) make slack as by lessening tension or firmness

• remit

1. (verb) become slow or slower

• weaken

2. (verb) make less active or fast

• decrease
• lessen
• minify

3. (verb) become looser or slack

• weaken

4. (verb) make slack as by lessening tension or firmness

• loose
• loosen

1. (verb) make slack as by lessening tension or firmness

• douse
• dowse

1. (verb) become slow or slower

• deceleration
• retardation
• slowing
• drop-off
• falling off
• falloff
• slack
• slump
• lag
• retardation
• slowdown

2. (verb) make less active or fast

• drop-off
• falling off
• falloff
• slack
• slump
• loosening
• relaxation
• slackening

3. (verb) make slack as by lessening tension or firmness

• loosening
• relaxation
• slackening

1. (verb) become looser or slack

• ease off
• ease up
• flag
• slacken off