noun
A person who habitually tries to stand out or be the center of attention, often with a slightly negative or teasing tone.
彼はいつも目立ちたがり屋で、すぐに冗談を言い始める。
He's always a show-off and quickly starts cracking jokes.
あの目立ちたがり屋がまた変な服を着てきた。
That attention seeker showed up in weird clothes again.
The verb phrase meaning 'to want to stand out'; 目立ちたがり屋 is the noun form for a person with that tendency.
Compound of 目立ち (continuative form of 目立つ 'to stand out') + たがり (from たがる, expressing desire) + 屋 (suffix for a person with a certain trait).