pompous

Where it comes from

Pompous came through French from Late Latin pomposus, stately or splendid, based on Latin pompa, a ceremonial procession, itself from Greek pompe, a sending or solemn procession.

How the meaning developed

Magnificent public display could be admired as stately, but display also invited criticism as ostentation. The negative judgment came to dominate, so pompous now usually means self-important or pretentiously grand.