A Lug (knob) is a typically flattened protuberance, a knob, or extrusion on the side of a vessel: pottery, jug, glass, vase, etc. They are sometimes found on prehistoric ceramics/stone-vessels such as pots from Ancient Egypt, Hembury ware, claw beakers, and boar spears.
A lug may also only be shaped as a lip for suspension–(no hole). In Ancient Egypt, lugs contained a hole for suspension, with 2– or 3–lugged vessels most common.
In Roman times, lugs were on some types of column-sections to aid in construction. After slung by rope into position with a crane, the lugs were then masoned off.