The tag alias #79022 stomach_ache -> upset_stomach is pending approval.

Reason: Essentially the same thing, merging them would reduce redundancy.

it might be a locale thing but i prefer stomach_ache
also since you made two similar alias requests, you can request a Bulk Update Request (BUR) for future reference instead

I really do not think these are interchangeable. Someone being in pain is not same as for example someone being nauseous.

I agree with Ruppari on this one, and was going to make a similar observation. To me stomach ache = stomach pain (most likely associated from overeating so it's stuffed/stretched, or from some types of illness esp if described by a youngster, or [rarely] from hunger pains). VS upset stomach = imminent/growing chance of vomit and/or diarrhea in the future with probably gas/bloating/nausea/indigestion happening currently.

The former is mainly about pain and the latter is mainly about nausea/gastrointestinal destabilization. They can overlap in some situations, but not always. And they often focus on different parts of the situation. So yeah, I wouldn't call them the same thing.

The Ak-shoo-ally: Stomachache is actually one word.

The take you might actually care about: As someone who has had frequent cases of both stomachaches and upset stomachs in the past, I have to back up the above. You don't need to have stomach pains to feel the nausea of an upset stomach, and you don't need to feel nausea for your stomach to ache.