Wiktionary
n. (context mathematics English) Any function whose value is unchanged if the independent variable changes sign i.e. ''f(x)'' = ''f(-x)''
Usage examples of "even function".
Obviously the Crypt can't even function without communications linkages to the outside world.
If she cannot even function at the paws of a kaiila what should one expect in one's own furs?
This flight will even function within an anti-magic area or shell (there are a couple of precedents for this unusual ability.
With hood and gloves it could even function as an emergency spacesuit.
Suit AIs helped fliers who wanted help, and they could even function as automatic pilots.
The moment she did, the vortex of heat consumed her, burning her from the inside out, robbing her of her ability to speak, to breathe, to even function.
Somewhere in the chain of command there must be a conscious, sober and sane human being who was actually doing his job, or the place couldn't even function on this level.
Without the influence of his aunt, he doubted if he could even function in society at all.
These keys are quite heavy and are carried over the shoulder, and can, if necessary, even function as weapons.
People with systems of delusions are often happy and can even function normally so long as those delusions do not come into conflict with reality.