Common everyday term for pain-relieving medicine, such as over-the-counter tablets or prescribed analgesics.
I had a headache, so I took a painkiller.
This painkiller works well.
Standard kanji spelling.
Search-only kanji form; not a standard spelling.
Compound of 痛み (itami, 'pain') + 止め (dome, 'stopping'), from the verb 止める (tomeru, 'to stop').