A state wherein one has the
desire of the mind - and/or a
response of the body merely
emulating such desire - to
get it on.
In men, symptoms include tumescence, erection, boner, havin' a roni, wood, satyriasis.
In women, symptoms include vaginal juices, lubrication, getting wet, nymphomania.
For both, see panting, shortness of breath, temporary blindness, abdication of responsibility, making babies.