My favourite words are the extremely long ones. Examples: antidisestablishmentarianism pneumonoultramicroscopicsilicovolcanoconiosis (longest word in the English language! woop woop woop) supercalifragilisticexpialidocious
Churlish - It pretty much means rude. Gargalesthesia - a long word for what it called to be "tickled"
I find it fun to say long, rhyming words repeatedly. e.g.: "Carrot parrot carrot parrot" "Bees knees peas seas bees knees peas seas"