■ noun ( plural nellies ) informal
1》 a silly person.
2》 derogatory an effeminate homosexual man.
Phrases
not on your ~ Brit. certainly not. [orig. as not on your Nelly Duff , rhyming sl. for 'puff' (i.e. breath of life); modelled on the phr. not on your life .]
Origin
1930s: from the given name Nelly .