It is the past tense of the verb "believe".
The fact that she supplied intricate details made her story quite believeable.
Clayton Moore Played the part much better and more believeable than John Hart.
part of speech
The part of speech for this particular word is a noun.
The part of speech for "answer" is a noun.
adverb
what part of speech is beneath
Strong believeable
The word believe does not have a prefix.
The part of speech for "explicit" is an adjective.
The part of speech for "twirl" is a verb.
The part of speech for "unfamiliar" is an adjective.