packsack vs knapsack

packsack and knapsack both are nouns.

Word	Noun	Adjective	Verb	Adverb
packsack	Yes	No	No	No
knapsack	Yes	No	No	No

As nouns, packsack and knapsack are synonyms defined as:

packsack and knapsack: a bag carried by a strap on your back or shoulder

Other synonyms of packsack include back pack, backpack, haversack, rucksack.

packsack (noun)	knapsack (noun)
a bag carried by a strap on your back or shoulder	a bag carried by a strap on your back or shoulder