Latin. literally, contempt for the things of the world. The aesthetic derives from the common spiritual belief (like the cycle of samsara in Buddhism) that the physical world is an overwhelming disappointment, poorly constructed, merely a testing-ground for humanity and/or a vast cosmic mistake.
While this would be considered heresy in the Church proper, many movements formed around this rejection of the physical world, both during the Middle Ages and today. The acute realization of the world's 'fallen' character then leads usually to disillusionment and psychic exhaustion, as the material/matter/flesh of the temporal realm consistently wither or fail. This can manifest itself in various forms, as with extreme Symbolism or abstraction in art, or alternatively in paranoia over the state of a flawed world (popular theme in science fiction).
This sense of fatalism then usually leads to a deisre for religious or spiritual transcendence, through escape, prayer, work or any (more recently) intellectualism or technology.
Recommended reading:
Bayle, P. (1647-1706) A general dictionary, historical and critical : a new and accurate translation of that of the celebrated Mr. Bayle, with the corrections and observations printed in the late edition at Paris is included : and interspersed with several thousand lives never before published : with reflections on such passages of Bayle, as seem to favour scepticism and the Manichee system. (London : J. Bettenham, 1734-1741. 10 v.)
O'Donnell, J. Avatars of the word : from papyrus to cyberspace (Cambridge: Harvard Press, 1998)
(...sorry about that title, sadly 18th. century treatises just tend to be like that...)