zasti -zat-za'i- gismu

x1 exists/is real/actual/reality for x2 under metaphysics x3.

Words usable for epistemology typically have a du'u place. x1 is physical (one sense). See also fatci, xanri.

In notes:

fatci
x1 (du'u) is a fact/reality/truth/actuality, in the absolute.
slabu
x1 is old/familiar/well-known to observer x2 in feature x3 (ka) by standard x4.
xanri
x1 [concept] exists in the imagination of/is imagined by/is imaginary to x2.
zatra'i
r1=z1 exists over interval r2.