laddie vs lad

laddie and lad both are nouns.

Word	Noun	Adjective	Verb	Adverb
laddie	Yes	No	No	No
lad	Yes	No	No	No

As nouns, laddie and lad are synonyms defined as:

Other synonyms of laddie include cub, sonny, sonny boy.

laddie (noun)	lad (noun)
a male child (a familiar term of address to a boy)	a male child (a familiar term of address to a boy)
	a boy or man