The noun 'sword' is a common noun, a general word for any kind of sword.
A proper noun is the name of a specific person, place, thing, or a title; for example:
Sword is not a concrete noun because sword is a common noun
proper
As a name of a road , Park Avenue', it is a proper noun, and both words star with a capital letter. However, when used separately, as 'the park, or 'the avenue', they are common nouns and so not need a capital letter.
Jupitermon does have something in common with Zyuranger's Daizyujin however that is only its Sword while it is in Wrath Mode since its Sword is huge which is similiar to the Sword that Daizyujin uses.
What sword? it could range from 3 lbs to 15 lbs. The common long sword (or war sword if you want to use the right name for it), was about 4 - 5 lbs and perfectly balanced. The greater swords (flamberge and claymore style), are more in the 10 - 15 lbs range, with the weight being in the handle and butt of the sword.
common
common and proper
It is a proper noun, because it is the name of a specific thing.
common
it's a common noun. a proper noun would be Spider-Man.
Proper
Pencil proper or common noun