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"
inspiring fear; "the formidable prospect of major surgery"; "a tougher and more redoubtable adversary than the heel-clicking, jackbooted fanatic"- G.H.Johnston; "something unnerving and prisonlike about high grey wall"
extremely impressive in strength or excellence; "a formidable opponent"; "the challenge was formidable"; "had a formidable array of compositions to his credit"; "the formidable army of brains at the Prime Minister's disposal"
showing skill and sensitivity in dealing with people; "by diplomatic conduct he avoided antagonizing anyone"; "a tactful way of correcting someone"; "the agency got the kid-glove treatment on Capitol Hill"
having or showing a sense of what is fitting and considerate in dealing with others; "she was tactful enough not to shatter his illusion"; "a tactful remark eased her embarrassment"
not easy; requiring great physical or mental effort to accomplish or comprehend or endure; "a difficult task"; "nesting places on the cliffs are difficult of access"; "difficult times"; "a difficult child"; "found himself in a difficult situation"; "why is it so hard for you to keep a secret?"
requiring much effort and trouble; "the mountain climb was long, steep, and difficult"
capable of or tending to change in form or quality or nature; "a mutable substance"; "the mutable ways of fortune"; "mutable weather patterns"; "a mutable foreign policy"
not at ease socially; unsure and constrained in manner; "awkward and reserved at parties"; "ill at ease among eddies of people he didn't know"; "was always uneasy with strangers"
causing inconvenience; "they arrived at an awkward time"
hard to deal with; especially causing pain or embarrassment; "awkward (or embarrassing or difficult) moments in the discussion"; "an awkward pause followed his remark"; "a sticky question"; "in the unenviable position of resorting to an act he had planned to save for the climax of the campaign"
not elegant or graceful in expression; "an awkward prose style"; "a clumsy apology"; "his cumbersome writing style"; "if the rumor is true, can anything be more inept than to repeat it now?"
lacking grace or skill in manner or movement or performance; "an awkward dancer"; "an awkward gesture"; "too awkward with a needle to make her own clothes"; "his clumsy fingers produced an awkward knot"
difficult to handle or manage especially because of shape; "an awkward bundle to carry"; "a load of bunglesome paraphernalia"; "clumsy wooden shoes"; "the cello, a rather ungainly instrument for a girl"