> as lemmas

1967 A. Wilson No Laughing Matter ii. 82 ‘I'm sorry?’ he asked with formal politeness.

1988 D. Waters Heathers (film script) (O.E.D. Archive) 13 Heather Chandler. You wanted to become a member of the most powerful clique in the school. If I wasn't already the head of it, I'd want the same thing.Veronica. I'm sorry? What are you oozing about?

2000 K. Atkinson Emotionally Weird (2001) 71 ‘I'm sorry?’ I said, thinking I must have mis-heard.

2007 P. Barker Life Class vi. 44 ‘I say, Tarrant, you're not chippy, are you?’ ‘I'm sorry?’ ‘Chippy. A bit, you know—’.