The noun 'stranger' is a singular, common, concrete noun, a word for a person.
The word 'stranger' is also the comparative form of the adjective strange.
proper
Yes
Proper noun
Yes
Yes.
Yes, it is a common noun, not a proper noun.
Stanley Cup is a proper noun.
Yes
Common
Common noun
Is security guard a proper noun
The noun spider is a common noun, a general word for a type of arachnid.A proper noun is the name of a specific person, place, or thing; for example, Spider-Man or the Spider House Cafe and Ballroom in Austin, TX.