The adjective form of triangle is triangular.
No, the noun triangle is a single word, not a compound noun.
Yes, it is. It is the adjective form of the noun treachery, which can mean villainy, perfidy, or disloyalty. But treacherous can also mean fraught with danger (a treacherous section of the road).
A Noun
No. In most cases, like "He tripped," it's a past tense verb. It can also be used as an adjective, notably in "a tripped breaker."
The adverb form of the adjective 'tragic' is tragically.
No, it is not. Triangle is a noun, a shape or anything with three sides. The adjective form is triangular.* In the popular historical term, triangle trade, it is acting as a noun adjunct in place of the adjective triangular.
The noun form for the adjective authentic is authenticity.
The noun form of the adjective 'dangerous' is dangerousness.The word 'dangerous' is the adjective form of the noun danger.The noun form of the adjective 'childish' is childishness.The word 'childish' is the adjective form of the noun child.The noun form of the adjective 'beautiful' is beautifulness.The word 'beautiful' is the adjective form of the noun beauty.
The noun form of the adjective 'wide' is wideness.A related noun form is width.
Triangular.
The noun form of the adjective 'comfortable' is comfortableness.The word 'comfortable' is the adjective form of the noun comfort.
The noun form of the adjective 'modest' is modestness.A related noun form is modesty.
The abstract noun form of the adjective unique is uniqueness.
The noun form for the adjective hilarious is hilariousness. A related noun form is hilarity.
The abstract noun form for the adjective convenient is convenience.
The noun form of the adjective 'considerate' is considerateness or consideration.
The adjective form for the noun nation is national.