'bunting' (cloth/flags) comes from Middle English (earlier forms like 'bonting' or 'bunting'), probably related to Germanic words for 'variegated' or 'coloured' cloth; the bird name 'bunting' was applied to small plump birds and may derive from the same root or from a dialectal word meaning 'small, plump one'.

'bunting' was used in Middle English to denote a type of cloth; over time the sense extended to cloth used for flags and decorations and then to the decorative flags themselves. The bird-name developed later by application to small seed-eating birds; the baseball sense (from the verb 'bunt') is separate and developed much later.

Initially used for a kind of cloth or fabric (often coloured), the word broadened to mean cloth used for decorative flags and then the flags themselves; extended senses include the name of small birds and, independently, the baseball term related to the verb 'bunt'.