Triarmed

A brace wire fastening for wire fences has been patented by Mr. Arthur Lott, of Riddleville, Tex. Combined with the panel wires are braces and triarmed clasps embracing the wires and braces at their points of intersection, the clasps each being made in one place, with its arms bent around a longitudinal or pasel wire and a brace wire.

Source: wiktionary

An abnormal arrangement of paired g chromatids resulting in a triarmed configuration Quadriradial (qr)

Source: wiktionary

Sequential living polymerizations of hydrophilic and hydrophobic vinyl ethers from these trifunctional initiators give amphiphilic triarmed block copolymers where the hydrophilic segments may be placed either inner or outer layer of the three arms.

Source: wiktionary