[Cyrien]

Your arguments are interesting but there are some holes in them. The sum of the parts is more than the parts themselves. Because a thing is made up partly of the thing it is supposed to be the opposite of does not mean it cannot still be its opposite.

One could make a strong argument for a dead horse being the opposite of a living horse and yet both are still horses.

And as to SE4 being or having a clock within it. I contend that that is just plain false. It makes use of a clock but is not itself a clock or have as one of its parts a clock. A clock may be necessary to use it as in the clock in the computer but simply making use of it does not make it a part of it.
Let us look at a generally accepted definition of clock so that we can begin to possibly view what may or may not be the opposite of a clock.

clock
n.
An instrument other than a watch for measuring or indicating time, especially a mechanical or electronic device having a numbered dial and moving hands or a digital display.
A time clock.
A source of regularly occurring pulses used to measure the passage of time, as in a computer.
Any of various devices that indicate measurement, such as a speedometer or a taximeter.
A biological clock.

This being the case it is clear that not all definitions can be true in all cases of what is a clock. Would some people perhaps argue that a watch is in fact a clock despite this defintion?

watch
A small portable timepiece, especially one worn on the wrist or carried in the pocket.

A chronometer on a ship.

So if a clock is not a watch can a watch be a clock? If not then anything of the above is not a clock. So what is a chronometer?

chro·nom·e·ter
n.
An exceptionally precise timepiece.

So what is a timepiece?

time·piece
n.
An instrument, such as a clock or watch, that measures, registers, or records time

Thus we have that a clock is something cannot be a watch but that measure time. But a watch can be a chronometer on a ship and a chronometer can be a clock. So by simply placing any clock on ship it simply ceases to be a clock?

With such variable and contradictory or almost contradictory definitions is it even possible to define what a clock is and thusly come to grips with what the opposite of a clock is?

I would therefore define the problem as thus. Clock is to vague a term. It applies to to many. It is like saying find the opposite to planet. One might be able to find the opposite to a planet but almost certainly can't to planet. The same holds true for clock. I could find the opposite for a specific instance of a clock but not to the wide range of things that clock itself might represent. Clock is merely a concept and as such it's only opposite is anti-clock which is a broad group just as clock is.

Why don't we have a unique desciptor for anti-clock then? Is it because it doesn't exist? Possibly. But more likely it is simply because we only name and make those things for which we have a use. A clock is usefull and has uses therefore an anti-clock must be useless and have no uses. Why would someone make a thing that must by its very nature is useless and has no uses? They wouldn't. That does not mean that such a thing does not exist it simply means that we have not made it ourselves and have no reason to define or know of it.