K-Word
The K-Word is a way to cover up any bad word starting with K. It's like a dirty little secret that everyone knows but no one talks about.
"He used the K-Word instead of 'knight' because he was too lazy."
"She called it the K-Word because it was easier than saying 'knight' out loud."
"They used the K-Word instead of 'kiss' because it was a dirty little secret."