To stretch; stretch one's muscles to make them more limber, as before exercise(verb)
To attach a limber(verb)
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Use "limber up" in a sentence
"He kneaded the earth with his feet as if he were a cat, trying to limber up his reluctant body."
"It was a relief to swim again and limber up his stiffened body, but to his astonishment he found that they were drawing near to an unfrequented portion of the city near the walls, and that the canal-street would soon turn off in another direction."
"On the second occasion the Washington Artillery, which was always getting into dangerous places, and often too near the covers of the enemy's sharp shooters, who seemed to take a special grudge against our gallant boys, was saved by a timely charge of the Crescents, who, pouring a heavy volley into the enemy, enabled the artillerists to limber up and haul off their pieces to the rear."