an atomizer to spray paint by means of compressed air
"The model used an airbrush to apply a smooth layer of foundation over her entire face."
A miniature, handheld paint sprayer, powered by compressed air or other gas, used for delicate, artistic painting, or sometimes retouching of photographs.
"The artist carefully selected a soft brush tip on her airbrush to apply the final layer of translucent watercolor over the portrait."
To paint using an airbrush.
"The special effects artist carefully airbrushed a layer of grey dust onto the actor's cheek to make him look older for the scene."