Yes, it can be.
The word part has a number of different meanings, but only one is an adjective, where it acts as the adjective partial, as in "He is part owner of the business."
It can be verb, in the usage, I part my hair on the left. (to comb hair)
It can be an adverb, in the usage, Obama is part Irish. (partly)
It can be a noun, in the usage, she plays the part of Juliet. (a role)
Or, I only like part of that book. (section, partial amount)
adjective
An adjective.
Adjective
An adjective
"Inexplicable" is an adjective.
Adjective
Adjective
adjective
It is an adjective.
Proud is an adjective.
Lazy is an adjective.
Vacuous is an adjective.