libido

Concise Oxford English Dictionary © 2008 Oxford University Press:
libido /lɪˈbiːdəʊ, lɪˈbʌɪdəʊ/

▶noun (pl. libidos)

• 1 sexual desire.

• 2 Psychoanalysis the energy of the sexual drive as a component of the life instinct.

– derivatives
libidinal adjective,
libidinally adverb.

– origin early 20th cent.: from L., lit. ‘desire, lust’.