let loose

{v.} 1a. or[set loose] or[turn loose] To set free; loosen or give up your hold on. * /The farmer opened the gate and let the bull loose in the pasture./ * /They turned the balloon loose to let it rise in the air./ 1b. or[turn loose] To give freedom (to someone) to do something; to allow (someone) to do what he wants. * /Mother let Jim loose on the apple pie./ * /The children were turned loose in the toy store to pick the toys they wanted./ 1c. To stop holding something; loosen your hold. * /Jim caught Ruth's arm and would not let loose./ Compare: LET GO, LET OUT. 2a. {informal} To let or make (something) move fast or hard; release. * /The fielder let loose a long throw to home plate after catching the ball./ 2b. {informal} To release something held. * /Those dark clouds are going to let loose any minute./ Syn.: CUT LOOSE, LET GO. 3. {informal} To speak or act freely; disregard ordinary limits. * /The teacher told Jim that some day she was going to let loose and tell him what she thought of him./ * /Mother let loose on her shopping trip today and bought things for all of us./ Syn.: CUT LOOSE, LET GO.