Leg
Leg turns up in 2 fields: welding, electrotechnology. Here is what it means to the people in each one.
Leg in welding
How far a fillet weld reaches along each member from the corner, the dimension used to call out fillet size.
Distance a fillet weld extends along each member, measured from the joint root to the toe on that side. An equal-leg 3/8 inch fillet has 3/8 inch legs and a theoretical throat of about 0.7 times that, roughly 0.265 inch. Legs are checked with fillet gauges, and long stretches of undersize leg are a common reject.
"Leg on that side is barely a quarter, print says five-sixteenths, add a pass."
Leg in electrotechnology
A single phase or branch of a polyphase electrical system.
A leg refers to one distinct phase conductor in a multi-phase power circuit, or one side of a split-phase system. In a three-phase system, technicians refer to the individual phases as legs. It is used to describe how loads are distributed or where a specific measurement is taken.
"We lost the B leg on that transformer, so it's single-phasing the motors downstream."