Meanings

gliding

dead letter

thinking one saw something that wasn't actually there

air pollution

air purifier

racing (of an engine)

emptiness is form

empty

empty

hollowing-out phenomenon

imitated cry (of an animal)

feigned laughter

empty shell

vacancy

(power of) imagination

groundless rumor or story (rumour)

air freight

aerial photograph

midair collision

virtual space (e.g. in computer graphics)