[v] become quiet or less intensive; "the fighting lulled for a moment"
[v] become quiet or calm, esp. after a state of agitation; "After the fight both men need to cool off."; "It took a while after the baby was born for things to settle down again."
[v] make calm or still; "quiet the dragons of worry and fear"
calm, chill out, cool it, cool off, lull, lull, quiet, quieten, settle down, simmer down, still, tranquilize, tranquillise, tranquillize