yes
Boastful is a word used to describe a noun, so yes, it is an adjective.
Boastful is the adjective of boastfulness.
The abstract noun form of the adjective boastful is boastfulness.The word boastful is the adjective form of the abstract noun boast.
The abstract noun form of the adjective 'proud' is proudness:"The proudness of the people..."A related abstract noun is pride:"The pride of the people..."
http://thesaurus.reference.com/browse/boastful There are some good entries here, just look at all the h-words.
The word boast is both a verb and an noun. Example uses: Verb: They boast about their ancestors but can their ancestors boast about them? Noun: That is a big boast, now you have to show us. Other noun forms are boaster, one who boasts, and boastfulness.
most boastful
When the boy went to school the next day, a boastful bully came up and said boastful things.
Braggy - an adjective derived from bragging - "boastful: exhibiting self-importance" Self-aggrandizing - To make oneself seem more splendid or glorious.
She thought she was a hero as she told us of her ventures; we just thought she was boastful.
You can use boastful in a sentence like this. Sam was very boastful after they won the game.
To "wax" is to speak eloquently. "Boastful" is bragging or talking about one's own accomplishments.
humble