'fiber' originates from Latin, specifically the word 'fibra', where 'fibra' meant 'a filament, fiber'.

'fibra' passed into Old French as 'fibre' and then into Middle English (various spellings such as 'fyber'), eventually becoming the modern English forms 'fiber' (US) and 'fibre' (UK); the verb and adjectival forms (e.g., 'fibered') developed from the noun.

Initially it meant 'a filament or thread'; over time the term retained that basic sense while extending to mean materials made of such filaments, biological fibers, and abstract/technical senses (e.g., 'fibered' as a structural or mathematical descriptor).