Two words that refer to something different AND are spelled differently are known as asynonyms. The goal is to find two words that have as little in common as possible, except for both being nouns perhaps.
"I found a nice example of asynonyms: Blackjack and dice."
"No way man, both are associated with 21 obviously. Fish and nostril are far better asynonyms."
"As if! Both relate to 'gooey'"
"Blackjack and nostril then?"
"No, both words have two syllables."