English definition of “length”
DISTANCE [C, U] › the measurement or distance of something from one end to the other: The carpet is over three metres in length. The length of the bay is roughly 200 miles. The village is so small that its entire length could be walked in 15 minutes.
TIME [C, U] › the amount of time something takes: the length of a film/play/speech Sitting still for any length of time is quite hard for most children.
WRITING [C, U] › the amount of writing in a book or document: He's written books of various lengths on the subject. All of your essays will be about the same length.
at length › If you talk about something at length, you talk for a long time: We discussed both topics at length.
PIECE [C] › a long piece of something: a length of cloth/cord/rope