一臂[ippi] (a) (helping) hand
三面六臂[sanmenroppi] rush of business
八面六臂[hachimenroppi] competent in all fields
猿臂[enpi] long, protruding elbows (like those of a monkey)

猿臂を伸ばす[enpiwonobasu] to stretch one's arms
半臂[hanpi] short-sleeved (or sleeveless) undergarment worn by aristocratic men
半臂の緒[hanpinoo] decorative gauze strap that hangs from the front left side of the kohimo when tying closed one's hanpi
猿臂打ち[enpiuchi] elbow strike (karate)