Loath vs. loathe

Loathe is a verb meaning to dislike greatly. For example, if you have a mean boss, you might say that you loathe him.

Loath is an adjective meaning unwilling or reluctant. For example, you might say that you are loath to spend time with your mean boss outside work.

If you have trouble remembering the difference between loathe and loath, try to associate the verb loathe with breathe, clothe, bathe, and teethe. Each of these has a corresponding noun that lacks the e. Loathe is a little different because loath is an adjective, not a noun, but this works as a memory trick nonetheless. – Grammarist.com