Like hell, #phrase.
Definition (informal): Very much (used for emphasis)
Examples:
1. My head hurts like hell.
2. All I know is that my mouth hurts like hell and I've about as much chance of getting in to see my dentist this week as I have getting into a size 10 dress.
3. I didn't really think about it much as I grew up, unless I bashed my hand against something then the tiny scar hurt like hell.
4. Either way, it hurts like hell on my right side when I breathe in.
5. It really is a magnificent bruise and I have no doubt it hurts like hell.
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Cambridge dictionary
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