(Sanskrit काम) Generally "lust, desire, sexual pleasure." It can also mean "beauty, loveliness, enjoyment, love or desire personified, wish, affection." Thus, kama can be positive or negative.
Kama is one of the four purusharthas (purposes of life).
"I am kama which is unopposed to Dharma." - Krishna in the Gita
Kama is one of the three granthis, knots of heart: Avidya, Kama and Karma (ignorance, desire, and action).
Q. Who is the greatest of all enemies?
A. Kama (desire), anger, untruth, greed and craving.
Q. Who is not gratified by (all) objects of (enjoyment)?
A. Desire (lust). - Shankaracharya