a cavity or passage in a tubular organ; "the lumen of the intestine"
a unit of luminous flux equal to the amount of light given out through a solid angle of 1 steradian by a point source of 1 candela intensity radiating uniformly in all directions
march aggressively into another's territory by military force for the purposes of conquest and occupation; "Hitler invaded Poland on September 1, 1939"
penetrate or assault, in a harmful or injurious way; "The cancer had invaded her lungs"
occupy in large numbers or live on a host; "the Kudzu plant infests much of the South and is spreading to the North"
a preliminary election where delegates or nominees are chosen
one of the main flight feathers projecting along the outer edge of a bird's wing
not derived from or reducible to something else; basic; "a primary instinct"
of first rank or importance or value; direct and immediate rather than secondhand; "primary goals"; "a primary effect"; "primary sources"; "a primary interest"