depth

The word “depth” means how far down something goes, from top to bottom or surface to floor. In plain terms, how deep something is, physically or in terms of thought and detail.

“Depth” is pronounced dehpth (/dɛpθ/ in IPA).

Here is “depth” used in a sentence: “The pool has a depth of two metres at the deep end.”

“Depth” is a noun.

The word “depth” comes from Old English. From Old English deopnes-related forms, built on "deep" plus the abstract suffix "-th" — the same pattern as "width" from "wide".

“Depth” is a fairly common word in modern English, usually learned at around the B1 level.

“Depth” has 3 distinct senses listed in this dictionary. The most common is: how far down something goes, from top to bottom or surface to floor.

Both measure distance in the up-and-down direction, but from opposite reference points. Height measures how far something rises upward, like a tower or a person. Depth measures how far something goes downward, like a pool or a well. The same pool has a height above the ground and a depth below the surface.

Yes, very often. Beyond literal distance downward, depth describes richness or intensity — depth of knowledge, emotional depth, or the depth of a character in a novel. Saying someone has depth means they are thoughtful and complex rather than shallow. The figurative sense borrows the idea of going far below the surface.

Depth is measured from the top or surface straight down to the bottom. For water you measure from the surface to the floor; for a hole, from ground level to its lowest point. It uses the same units as any length — metres, feet, or centimetres — just taken in the downward direction.