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to loosen; to slacken
to relax (attention, efforts, etc.); to let down (one's guard); to relieve (tension)
to relax (a rule); to ease (e.g. restrictions); to loosen (control)
to reduce (speed); to slow down; to ease up
to make more gradual (of a slope)
食後にベルトを少し緩めてください。
Please loosen your belt a little.
規制を緩めるべきだという意見がある。
There are opinions that regulations should be relaxed.
ネジを少し緩めてみた。
I tried loosening the screw a little.