Aviation Dictionary
بال یا رول برینگ (یاتاقان) ضد اصطکاک
Any bearing that supports a rotating shaft with a rolling contact, rather than a sliding contact. Ball bearings, roller bearings, and needle bearings are all antifriction bearings. Plain bearings and bushings which support rotating shafts with a sliding contact between the bearing and the shaft are called friction-type bearings.