#1 loosen up v. cause to become unblocked; "The medicine unstuffed my nose in minutes!". wn #2 loosen up v. become less tense, less formal, or less restrained, and assume a friendlier manner; "our new colleague relaxed when he saw that we were a friendly group". wn #3 loosen up v. make one's body limber or suppler by stretching, as if to prepare for strenuous physical activity. wn #4 loosen up v. become less tense, rest, or take one's ease; "He relaxed in the hot tub"; "Let's all relax after a hard day's work". wn #5 loosen up v. cause to feel relaxed; "A hot bath always relaxes me". wn