sneeze āļāļ·āļāļāļ°āđāļĢ sneeze āļāļ·āļāļāļ°āđāļĢ To expel air forcibly from the mouth and nose in an explosive, spasmodic involuntary action resulting chiefly from irritation of the nasal mucous membrane.An instance or the sound of sneezing.sneeze at Informal To treat as unimportant: These deficits are nothing to sneeze at.