nail

Concise Oxford English Dictionary © 2008 Oxford University Press:
nail/neɪl/

▶noun

• 1 a small metal spike with a broadened flat head, driven into wood to join things together or to serve as a hook.

• 2 a horny covering on the upper surface of the tip of the finger and toe in humans and other primates.

  ■ a hard growth on the upper mandible of some soft-billed birds.

• 3 a former measure of length for cloth, equal to 2 1/4 inches.

• 4 a former measure of wool, beef, or other commodity, roughly equal to 7 or 8 pounds.

▶verb

• 1 fasten with a nail or nails.

• 2 informal detect or catch (someone, especially a suspected criminal).

• 3 informal (in sport) strike (a ball) forcefully and successfully.

  ■ Baseball (of a fielder) put (a runner) out by throwing to a base.

  ■ chiefly N. Amer. (of a player) defeat or outwit (an opponent).

• 4 (nail someone down) elicit a firm commitment from someone.

• 5 (nail something down) identify something precisely.

– phrases
a nail in the coffin an action or event likely to have a detrimental or destructive effect.
on the nail (N. Amer. also on the barrelhead) (of payment) without delay.

– derivatives
-nailed adjective,
nailless adjective.

– origin OE nægel (n.), næglan (v.), of Gmc origin.