Thanks for using this online dictionary, we have been helping millions of people improve their use of the english language with its free online services. English definition of arm is as below...
Arm (n.) The end of a yard; also, the part of an anchor which ends in the fluke..
Tuck ::
Tuck (v. t.) To inclose; to put within; to press into a close place; as, to tuck a child into a bed; to tuck a book under one's arm, or into a pocket..