sniffer

intransitive verb

1. to draw in air through the nose with enough force to be heard, as in clearing the nose or smelling something
2. to express disdain, skepticism, etc. by sniffing

transitive verb

1. to breathe in forcibly through the nose; draw in or inhale nasally
2. to smell (a substance) by sniffing
3. to detect, perceive, or get a suspicion of by or as by sniffing: often with out

noun

1. an act or sound of sniffing
2. something sniffed