difficult to penetrate; incomprehensible to one of ordinary understanding or knowledge; "the professor's lectures were so abstruse that students tended to avoid them"; "a deep metaphysical theory"; "some recondite problem in historiography"
requiring more than usually expected or thought due; especially great patience and effort and skill; "found the job very demanding"; "a baby can be so demanding"
your overall circumstances or condition in life (including everything that happens to you); "whatever my fortune may be"; "deserved a better fate"; "has a happy lot"; "the luck of the Irish"; "a victim of circumstances"; "success that was her portion"