I am not the best speller or grammar nazi in the world and I have a few words that I absolutely hate to spell, I nearly always get them wrong
collection (it just never ever looks correct)
theirs and theres (I always get them mixed up)
definitely (I always spell it definately)
I have a couple more but I have had too many drinks to remember them at this moment hahaha
Funny story a friend of mine is a grammar/spelling nazi and we were talking about how I hate definitely and I always spell it wrong, so he jumps up on his high horse oh that's an easy one definately hahaha I nearly fell over dead and he was very ashamed when he realised that he spelt it wrong hahahah.