I. snif ‧ fle 1 /ˈsnɪf ə l/ BrE AmE verb [intransitive] spoken
[ Date: 1600-1700 ; Origin: sniff ]
to keep sniffing in order to stop liquid from running out of your nose, especially when you are crying or you have a cold:
For goodness’ sake, stop sniffling!
II. sniffle 2 BrE AmE noun
have the sniffles spoken if you have the sniffles, you keep sniffing, especially because you have a cold