Meaning of “sniff” - Learner’s Dictionary

sniff

verb uk us /snɪf/
BREATHE [ I ]

to breathe air in through your nose in a way that makes a noise:

Sam had a cold and she kept sniffing.
SMELL [ I, T ]

to breathe air in through your nose in order to smell something:

She sniffed the flowers.
sniff noun [ C ]

(Definition of “sniff” from the Cambridge Learner’s Dictionary © Cambridge University Press)