What's the proper term for word endings? (read and it will make sense I promise)

[Flamesparrow]

Messing about with the kids, told DD1 I had kissed DS because he is pretty (prob scarred her for life ), anyway, she said she was prettier, so then he piped up that he was prettiest, and I was trying to say I was impressed with his choice of ....... (word ending) as he'd chosen the one she couldn't top, but all I could think of was tense and that clearly isn't the right word.

See. Clear as mud

suffix?

suffix

Comparative (prettier) and superlative (prettiest) adjectives.

And now Daisymoo has chosen the answer that I can't top.

turned up to say suffixes, but tc and co have beaten me to it

Superlatives are just Awesome

Fabulous