No, it's a preposition.
Direct can be an adjective, a verb and an adverb. Adjective: Without interruption/Straight. Verb: To control/To aim. Adverb: Directly.
The word worst *is* an adjective. It is the superlative of the adjective "bad" (bad-worse-worst). It can also be a noun if used without a following noun (the worst).
The word our is a possessive adjective. It is classified as a pronominal limiting adjective, but of the possessive adjectives that are so classed, only "his" can be used without a following noun.
malleable
Yes, it means without flaw or error.
State is a noun and an adjective without any changes of the form.
no dough
It is an adjective (without end, or tediously long). The adverb form is endlessly.
Yes, the word 'penniless' is an adjective, a word that describes a noun as without a penny.
Direct can be an adjective, a verb and an adverb. Adjective: Without interruption/Straight. Verb: To control/To aim. Adverb: Directly.
The word nonstop can be an adjective and an adverb. It means without stopping.
The word "hopeless" meaning without hope (also futile or useless) is an adjective.
faceless means "without a face"
colourfulterrificfabulousbeautifulawesome
The answer is mere
It can be, but without is almost always a preposition. It acts like an adjective or adverb when the object is omitted. It is most clearly an adverb when used in the pairing "within and without" which refers to an adjective. It is not clearly an adverb in the usual example "to do without" (something).
The word definite is an adjective. It means without any doubt.