A suffix is an element of a language that is added to the end of a word. E.g. -ly is a suffix often found at the end of adverbs: really, quickly, happily, strangely, etc., -d/-ed is a suffix often found at the end of a verb to denote the simple past: used, bruised, grazed, heated, etc.
Ordering a gravestone and want to make sure the suffix is used correctly. While the last name is on the bottom to be shared by spouse, I need to put Edward H. II up top. The proper name is Edward ...