The word 'whooshing' is a prime example of linguistic onomatopoeia, derived from the earlier verb 'whoosh' which first appeared in English in the mid-19th century. It is an imitative or expressive formation, created to phonetically replicate the sound of a sudden rush of air or water, or of an object moving swiftly through the air. This process of sound symbolism connects the sensory experience directly to the word's form, bypassing the need for classical roots. The addition of the '-ing' suffix follows standard English grammatical rules to form its present participle or gerund forms, allowing it to function as an adjective or a noun describing the ongoing action or characteristic sound.

This is an onomatopoeic word, formed to imitate the sound it describes. It is not productively built from separate, meaningful morphemes in English.