1 measurement or extent from end to end; the greater of two or the greatest of three dimensions of a body.
2 extent in, of, or with regard to, time (a stay of some length; the length of a speech).
3 the distance a thing extends (at arm's length; ships a cable's length apart).
4 the length of a horse, boat, etc., as a measure of the lead in a race.
5 a long stretch or extent (a length of hair).
6 a degree of thoroughness in action (went to great lengths; prepared to go to any length).
7 a piece of material of a certain length (a length of cloth).
8 Prosody the quantity of a vowel or syllable.
9 Cricket a the distance from the batsman at which the ball pitches (the bowler keeps a good length). b the proper amount of this.
10 the extent of a garment in a vertical direction when worn.
11 the full extent of one's body.
Phrases and idioms:
at length
1 (also at full or great etc. length) in detail, without curtailment.
2 after a long time, at last.
Etymology: OE lengthu f. Gmc (as LONG(1))
Useful english dictionary. 2012.