The word singular is an adjective. It means to be the only one or unique.
The word minion is a singular noun. The plural form is minions.
The word cossacks is a plural noun. The singular is cossack.
The word boiler is a singular noun. The plural is boilers.
The word mutiny is a singular noun. The plural form is mutinies.
"Mar" can be a noun, a verb, or a proper noun. It depends on the context in which it is used.
What is has's part of speech? means What is the part of speech of 'has'?The answer is that it is a verb: 'has' is the third person singular present tense of the verb 'to have'.
Noun, Plural or singular
Noun singular Noun plural Verb (third person singular)
The word minion is a singular noun. The plural form is minions.
AstroTurfs is a plural noun. The singular is AstroTurf.
The word lots is a plural noun. The singular is lot.
The word instructions is a plural noun. The singular is instruction.
The word presidios is a plural noun. The singular is presidio.
The word vices is a plural noun. The singular is vice.
The word authorship is a singular noun. The plural is authorships.
The word vacation is a singular noun. The plural is vacations.
The word buoys is a plural noun. The singular is buoy.