'bandwidth' originates from modern English as a compound of 'band' and 'width', formed to describe the 'width' of a frequency 'band' used in radio and telecommunication.

'bandwidth' emerged in technical contexts in the early 20th century (radio and telegraphy). The element 'band' goes back to Old English/Old Norse words meaning a strip or range ('band'), and 'width' comes from Old English 'wīdþu' (related to 'wide'), combined into the modern technical term.

Initially it meant the literal 'width' of a frequency band; over the 20th century it broadened to mean overall data-carrying capacity and later acquired figurative uses referring to personal or organizational capacity.