Ailevators are the trailing edge roll control surfaces of a wing that also lift or drop for pitch control. It is correct terminology on a flying wing (ie. Northrup, Horten, etc.)
I'll agree to disagree, as there are mixed terms depending on aircraft. For flying wings, elevon is the better description IMO. Here's an example of two terms describing the same function, courtesy of the RC Sailplane Glossary:
<a name="ailevator"><font size="5">Ailevator</font></a> -
This is a new term that has sprung up with the advent of the newer computer radio control systems. It is where each elevator in a standard (conventional) or v-tail moves independently, like ailerons on a wing. In addition to each elevator side moving up and down together, each side moves in opposite directions when moving as an ailevator. On a
<font color="#0066cc">v-tail</font>, this is also known as a
<font color="#0066cc">ruddervator</font>, as they can serve the same purpose. Typically, both ailevators and ailerons are coupled together to maximize roll performance, especially on larger wingspan planes.
<a name="elevon"><font size="5">Elevon</font></a><a name="elevons"> -
</a> Elevon is a term that means both aileron and elevator combined into the same control surface. It is used on tailless aircraft such as as flying wings. Like ailerons, an elevon provides for a plane's roll control by moving in opposite directions and like an elevator, provides pitch control by moving up and down together. In order for a plane to have elevons either a computer r/c system is needed or a
<font color="#0066cc">mixer</font> (either electronic or mechanical). This movement is very similar to what happens in a
<font color="#0066cc">V-Tail</font> setup.
Whether a tailless aircraft has a vertical fin and rudder or not, when the ailerons are also used for pitch, 'elevon' should be correct. When the elevator halves are combined for roll and pitch, that becomes ailevators. I have a foam F-86 that has ailevators. One could argue they mean the same thing, but the true ailevator aircraft doesn't have elevons.
There used to be an Austrailian company that made a stand-alone elkectronic mixer (for Zagi wings) that didn't need a computerized transmiter mixing.
I have an Ace mixer, also a device called a D.A.D. that does the same, both gathering dust since the '80's. [8D] BTW, Bill Evans, king of tailless aircraft, refers to them as 'elevons'. I still have a Slo-Motion from his 'Simitar' series, a great flier!