ostentatiousness n lack of elegance as a consequence of being pompous and puffed up with vanity Usage(s) In these troubled times, ostentatiousness is out, austerity in. Though in her cut-away interviews Posh professed to find the ladies charming, the clip was clearly edited to both ogle at the women's wealth and laugh at their ostentatiousness. Synonym(s) ostentation pomposity pompousness pretentiousness puffiness splashiness inflation