To draw air through the nose in short audible inspirations, as an expression of scorn; snuff: often with at.To draw in with the breath through the nose; smell of with an audible inhalation; snuff: as, to sniff the fragrance of a clover-field.To perceive as by snuffing; smell; scent: as, to sniff danger.To draw the breath through (the nose) in an unpleasantly audible manner.n. The act of sniffing; a single short audible inspiration through the nose.n. Perception of smell obtained by inhaling audibly; that which is taken by sniffing: as, a sniff of fresh air.n. The sound produced by passing the breath through the nose with a quick effort; a short, quick snuffle.