barbecuing vs roasting

barbecuing and roasting both are nouns.

Word	Noun	Adjective	Verb	Adverb
barbecuing	Yes	No	No	No
roasting	Yes	No	No	No

As nouns, roasting is a hypernym of barbecuing; that is, roasting is a word with a broader meaning than barbecuing:

barbecuing: roasting a large piece of meat on a revolving spit out of doors over an open fire
roasting: cooking (meat) by dry heat in an oven (usually with fat added)

barbecuing (noun)	roasting (noun)
roasting a large piece of meat on a revolving spit out of doors over an open fire	cooking (meat) by dry heat in an oven (usually with fat added)