There's a word for it, can't remember?

Empirical—relying on or derived from observation or experiment: empirical results that supported the hypothesis. Verifiable or provable by means of observation or experiment: empirical laws. Guided by practical experience and not theory, especially in medicine.

‘Authenticated’ comes to mind. As does legitimate, validated, bona fide, the real McCoy, documented, substantiated, proven, evidenced, corroborated, confirmed, accredited, endorsed.

Science.

Reality.

Scientific Hypothesis

Hypothesis means speculation (or theory). Reality and science, and all the words given by @Skylight would be synonymes, but I think @Pachyderm_In_The_Room ‘s word would be the best match. While hypothesis means theoretically, empirical means proven – the proof to support the hypothesis.

” theory or speculation ”

@Pachyderm_In_The_Room Answered your question but I think you have a fuzzy idea about theory.

Any good dictionary gives the scientific meaning of theory ( NOT linked to speculation, or opposed to empirical ) as it’s primary meaning.

To add to @Neodarwinian‘s comment – in science, “empirical” is kind of an insult. It’s like the scientific equivalent of “anecdotal”.

Practical, experiential knowledge is empirical not theoretical.

Factual, evidential or experiential?

speculation

@glacial Not according to the dictionary. I was not familiar with the word “empirical” so had to look it up:

“based on, concerned with, or verifiable by observation or experience rather than theory or pure logic.
“they provided considerable empirical evidence to support their argument”
synonyms: experiential, practical, heuristic, firsthand, hands-on.”

@Skaggfacemutt I’m talking about the kind of nuance which comes with working in a scientific field. An “empirical” study will always be considered less interesting than one based on theory. The applications of the results of an empirical study are limited to that site or that species or that situation alone. The results of a study based on (for example) modelling will be applicable over a wide range of situations. So, I’ll hear people in my field say all things like, “Yeah, but it’s just an empirical study” all the time – the implication being that the study has extremely limited usefulness or impact. That’s what I mean by it being kind of an insult.

@glacial Thank you for that. So, with that in mind, I think the answer to the original question would indeed be “empirical.” Do you agree?

@Skaggfacemutt Yes, I agree that is probably the word that the OP is looking for.

However, when the OP (along with several other jellies who followed suit) puts the word “theory” into the same category as “speculation” while elevating “empirical” to the same category as “real”, that indicates a lack of understanding of how these terms are used in science. That’s what @Neodarwinian and I are responding to.

To people who don’t have a science background, “theory” is a word that inspires suspicion, while something “empirical” is trustworthy and always factual. In science, exactly the opposite is true.

Based on the number of us who agree on “empirical,” I have empirical evidence that it may be a good word choice for @mazapan.

Then again, since we’ve never heard again from him/her, maybe not. ;-)