In reply to:

what would or could time be, if not linear?
Spatial.
And I don't care if the OED does say "spatial as opposed to time" ... what do they know, anyway,
except what we tell them.
If time isn't spatial then why do authors and scientist talk about the space-time continuum and doors
to other times and space portals and E =MC squared and all that stuff?
Huh? Huh?

the space-time continuum refers to the four "standard" dimensions; i.e., the three dimensions of space plus time, but. there appear to be "discontinuities" in the space-time continuum, such as the origin of space-time (the Big Bang, if you like). one explanation for this comes from Stephen Hawking (see 'A Brief History of Time') in the form of "imaginary time", which flows at right angles to ordinary time!
http://library.thinkquest.org/27930/time.htm