Definition of snivels:
(v) :
(derogatory, intransitive) To cry while sniffling; to whine or complain while crying.
(v) :
(derogatory, transitive) To say (something) while sniffling or crying.
(v) :
(intransitive) To breathe heavily through the nose while it is congested with nasal mucus.
(n) :
The act of snivelling.
(n) :
Nasal mucus; snot.