sneeze 
(snēz)
(snēz)intr.v. sneezed, sneez·ing, sneez·es
To expel air forcibly from the mouth and nose in an explosive, spasmodic involuntary action resulting chiefly from irritation of the nasal mucous membrane.
n.
Phrasal Verb: An instance or the sound of sneezing.
sneeze at Informal
To treat as unimportant: These deficits are nothing to sneeze at.
[Middle English snesen, alteration of fnesen, from Old English fnēosan; see pneu- in the Appendix of Indo-European roots.]
sneezer n.
sneezy adj.