mental

The definition of mental is relating to the mind or to problems of the mind.

(adjective)

An example of mental used as an adjective is the phrase a mental process which means a process that occurs in the mind.
An example of mental used as an adjective is the phrase a mental illness which means a sickness in the mind.

See mental in Webster's New World College Dictionary

adjective

of or for the mind or intellect: mental powers, mental aids
done by, or carried on in, the mind (i.e., without using written symbols): mental arithmetic
1. of, having, or related to mental illness or any psychiatric disorder: a mental patient, mental health
2. Informal mentally deranged; insane
for the mentally ill: a mental hospital
having to do with mind reading, telepathy, etc.

Origin: ME < MFr < LL mentalis < L mens (gen. mentis), mind

Related Forms:

adjective

of the chin

Origin: < L mentum, the chin < IE base *men-, to project + -al

See mental in American Heritage Dictionary 4

adjective

Of or relating to the mind; intellectual: mental powers.
Executed or performed by the mind; existing in the mind: mental images of happy times.
Of, relating to, or affected by a disorder of the mind.
Intended for treatment of people affected with disorders of the mind.
Of or relating to telepathy or mind reading.
Slang
a. Emotionally upset; crazed: got mental when he saw the dent in his new car.
b. Offensive Slang Mentally or psychologically disturbed.