The word 'bubble' is both a verb (bubble, bubbles, bubbling, bubbled) and a noun (bubble, bubbles). The adjective form is bubbly.
The word 'bubble gum' is a compound noun, an open spaced compound noun; two words joined to form a noun with its own meaning.
Noun or adjective
Barbadian can be a noun and an adjective. Noun: Someone from Barbados. Adjective: Of, or relating to, Barbados.
The word "silent" can function as both an adjective and a noun.
The word "ultimate" can function as an adjective or a noun. As an adjective, it means "definitive" or "final." As a noun, it refers to the final or highest part in a sequence or growth.
Monotonous is an adjective.
Noun or adjective
Invisibility is a noun.
The word lemon can be a noun and an adjective. The word car is a noun.
University is a noun.
Civil is an adjective. civil authorities - adjective + noun civil liberties - adjective + noun
Colorful is an adjective, a word that describes a noun.
The word scientific is an adjective, not a noun. The adjective scientific is not capitalized unless it is part of a proper name.
It can be a noun or adjective.
It is an adjective.
Noun
Adjective
The word lemon can be a noun and an adjective. The word car is a noun.