be death on someone—(coll.)
1. be fatal to a person; be very effective in acting against smb.:
- The new teacher is death on students who come late to class.
2. be very fond of a person:
- Fanny hasn’t forgotten you … she was always death on you English chaps.
Note: The expression does not correlate in meaning with the phrase die on someone—(also: go dead on someone)
1. die while in the charge or care of a person:
- “I want to look after her while she’s in England.” “Suppose she died on you?”
2. (of an apparatus, appliance, etc. in smb.’s care) break down; cease to function:
- My car died on me, and I couldn’t get it started.
be the death of someone—(coll.)
1. said of things (especially done repeatedly) which upset or irritate a person:
- Forty, if she’s a day, wears pince-nez and an air of brisk efficiency that will be the death of me.
2. said of smb. who is exceptionally funny or ridiculous:
- Lili’s capering seemed the funniest thing she had ever seen. “Stop, Lili, stop! You’ll be the death of me!”