plural of stolen base

(baseball) Having a baserunner on first base, second base, and third base.

plural of on-base percentage

(baseball) The frequency with which a hitter successfully reaches first base.

(roofing) Plies or strips of roof membrane material used to close-off and/or seal a roof at the horizonta-to-vertical intersections. Membrane base flashing covers the edge of the field membrane.

(roofing) an impregnated, saturated, or coated felt placed as the first ply in some low-slope roof systems.

plural of fan base

(US, informal) To base on.

plural of air base

plural of power base