edge

Concise Oxford English Dictionary © 2008 Oxford University Press:
edge/eʤ/

▶noun

• 1 the outside limit of an object, area, or surface.

  ■ an area next to a steep drop.

• 2 the sharpened side of a blade.

• 3 an intense or striking quality.

  ■ a quality or factor which gives superiority over close rivals: his cars have the edge over his rivals'.

• 4 the line along which two surfaces of a solid meet.

▶verb

• 1 provide with a border or edge.

• 2 move carefully or furtively.

• 3 (usu. edge out) informal defeat by a small margin.

• 4 give an intense or sharp quality to.

• 5 Cricket strike (the ball) with the edge of the bat.

– phrases
on edge tense, nervous, or irritable.
set someone's teeth on edge (of a sound or taste) cause intense discomfort or irritation to someone.

– derivatives
-edged adjective,
edgeless adjective,
edger noun.

– origin OE ecg ‘sharpened side of a blade’, of Gmc origin.