'windborne' originates from Modern English compounding of 'wind' and the past participle 'borne' (from Old English 'beran' meaning 'to carry').

'wind' comes from Old English 'wind', and 'borne' is from Old English past participle 'boren' of 'beran' ('to carry'); the compound 'wind-borne' / 'windborne' developed in later English to describe things carried by the wind.

Initially it meant literally 'carried by the wind', and this core meaning has remained largely unchanged, though usage has extended to airborne transmission (e.g., pollen, ash, pathogens).