From Wiktionary, the free dictionary
Gryffindor + -ish
Gryffindorish (comparative more Gryffindorish, superlative most Gryffindorish)
- Of, related to, or exhibiting traits associated with Gryffindor house from the Harry Potter series such as bravery, boldness, and being extroverted.
2004 September 2, Rick R., “Re: Sorting LOTR characters (was: just for the heck of it(”, in alt.fan.harry-potter[1] (Usenet):The most Gryffindorish character Tolkien wrote about.
2007 May 2, Bonehammer, “Re: (Ex) Students behaving out of character with their house”, in alt.fan.harry-potter[2] (Usenet):Peter/Wormtail has not shown any Gryffindorish trait so far.
2007 May 4, drusilla, “Re: (Ex) Students behaving out of character with their house”, in alt.fan.harry-potter[3] (Usenet):Being arrogantly pretentious is a very Gryffindorish trait ;)