the.com/width

The dimension nobody measures until the couch doesn't fit through the door.

means The measurement of how far something extends from side to side.

from Width is a fairly late addition to English, built in the 1600s from 'wide' plus the suffix '-th' (the same pattern that gave us depth from deep, and warmth from warm). Before that, English just made do with 'wideness.' So width isn't ancient — it's a tidy, somewhat artificial coinage, made on the spot because people needed a noun to match 'wide' the way 'long' already had 'length.'

math default
In geometry, width is the shorter of two dimensions, by convention.
screen specs
TVs list width first, which is why none fit your wall.
CSS trap
Width 100 percent can still overflow thanks to padding and borders.
etymology
From Old English wid, meaning wide, same root as wide.
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