Misanthropic

From the noun 'misanthrope' a person who dislikes and avoids other people. From the Greek misein - 'to hate' and anthropos - 'man'.

'Despite the smile on his face, Big John was taking his misanthropy just a bit too far.'

I have liked this word since studying Molière's Le Misanthrope when at university and giving the impromptu description: 'The misanthrope is just a miserable, old geezer who sits in the corner going "bleurgh".' Not sure if this was a degree-standard observation but it caused a chuckle and it coincides wonderfully with image I have in my head.
It's another word I would like to see brought back into common usage. Perhaps to replace the awful Americanism that is 'party-pooper'. For example: 'Stop being such a misanthrope and come to the pub.' I can't really see it happening but we can but hope.