All dictionaries I've looked at (MW, OED, Cambridge) define painkiller broadly as any drug that relieves pain. Do you have a source for your claim that it's use

All dictionaries I've looked at (MW, OED, Cambridge) define painkiller broadly as any drug that relieves pain. Do you have a source for your claim that it's used narrowly? Here's mine: https://www.merriam-webster.com/dictionary/painkiller https://www.merriam-webster.com/dictionary/painkiller