1.
If you describe something as ~, you disapprove of it because it is expensive and is intended to impress people. (FORMAL)
...an ~ wedding reception.
ADJ disapproval
2.
If you describe someone as ~, you disapprove of them because they want to impress people with their wealth or importance. (FORMAL)
Obviously he had plenty of money and was generous in its use without being ~...
ADJ disapproval
~ly
Her servants were similarly, if less ~ly attired.
ADV
3.
You can describe an action or behaviour as ~ when it is done in an exaggerated way to attract people’s attention.
His wife was fairly quiet but she is not an ~ person anyway.
ADJ: usu ADJ n
~ly
Harry stopped under a street lamp and ~ly began inspecting the contents of his bag.
ADV: usu ADV with v