Can you define what so-called "matter" is without going in semantic circles

Question

Much of our scientific ideas, concepts, interpretations, etc, have a 'support system' of sorts based on the concept of "matter." As of yet it seems that there is no clear, definitive definition of this highly elusive "stuff," or even proof that it exists at all, yet people continue to believe it's real. Ergo, I must side with Bishop George Berkeley in holding that this thing called "matter" simply does not exist... Can you convince me otherwise? (Bet you can't... make sure you look up the words you want to use before writing an answer; no circular arguments please).

Answer 1

Can you define ANYTHING without going in semantic circles?

Describe love without describing hate.  Describe any emotion without siting another emotion as reference.

Describe "tall" without necessarily defining or eluding to a "short".

Our minds are too small not to think in opposites.  Where there is a yin we must also see a yang.

Answer 2

Anything which distorts space/time.

Space/time being non-material; a dimension. Matter exists in space/time and distorts it, or so Einstein would have me believe.

I'm happy to refine in light of criticism.

EDIT: I'm assuming that since I don't refer to energy you're good with me not going on to define it.

Answer 3

All contributions are fron the Urantia Papers where "matter" is used 432 time.

P.9.4 "Power is ordinarily limited to the designation of the electronic level of material or linear-gravity-responsive matter in the grand universe."

"P.9 - §8 2. Emergent energy embraces those energies which are responsive to Paradise gravity but are as yet unresponsive to local or linear gravity. This is the pre-electronic level of energy-matter."

"P.9 - §9 3. Universe power includes all forms of energy which, while still responding to Paradise gravity, are directly responsive to linear gravity. This is the electronic level of energy-matter and all subsequent evolutions thereof."

"Gravity is the sole control of energy-matter."

Note: Matter seems to be a form of energy. I have heard it expressed as Matter is energy slowed.

Answer 4

How about a standing wave... or at least that's what someone called it once...but I prefer "stuff"...

Answer 5

coalesced energy

Answer 6

...It is normally defined as anything that has mass and takes up space.