Etymology: Middle English, from Old English heard; akin to Old High German hart hard, Greek kratos strength
Date: before 12th century
1 a: not easily penetrated : not easily yielding to pressure bof cheese: not capable of being spread : very firm 2 aof liquor(1): having a harsh or acid taste (2): strongly alcoholic b: characterized by the presence of salts (as of calcium or magnesium) that prevent lathering with soap <hard water> 3 a: of or relating to radiation of relatively high penetrating power : having high energy <hard X rays>b: having or producing relatively great photographic contrast <a hard negative> 4 a: metallic as distinct from paper <hard money>bof currency: convertible into gold : stable in value c: usable as currency <paid in hard cash>dof currency: readily acceptable in international trade e: being high and firm <hard prices> 5 a: firmly and closely twisted <hard yarns>b: having a smooth close napless finish <a hard worsted> 6 a: physically fit <in good hard condition>b: resistant to stress or disease c: free of weakness or defects 7 a (1):firm, definite<reached a hard agreement>(2): not speculative or conjectural :factual<hard evidence>(3): important or informative rather than sensational or entertaining <hard news>b:close, searching<gave a hard look>c: free from sentimentality or illusion :realistic<good hard sense>d: lacking in responsiveness :obdurate, unfeeling<a hard heart> 8 a (1): difficult to bear or endure <hard luck><hard times>(2):oppressive, inequitable<sales taxes are hard on the poor><a hard restriction>b (1): lacking consideration, compassion, or gentleness :callous<a hard greedy landlord>(2):incorrigible, tough<a hard gang>c (1): harsh, severe, or offensive in tendency or effect <said some hard things>(2):resentful<hard feelings>(3):strict, unrelenting<drives a hard bargain>d:inclement<hard winter>e (1): intense in force, manner, or degree <hard blows>(2): demanding the exertion of energy : calling for stamina and endurance <hard work>(3): performing or carrying on with great energy, intensity, or persistence <a hard worker>f: most unyielding or thoroughgoing <the hard political right> 9 a: characterized by sharp or harsh outline, rigid execution, and stiff drawing b: sharply defined :stark<hard shadows>c: lacking in shading, delicacy, or resonance <hard singing tones>d: sounding as in arcing and geese respectively —used of c and ge: suggestive of toughness or insensitivity <hard eyes> 10 a (1): difficult to accomplish or resolve :troublesome<hard problems><the true story was hard to come by>(2): difficult to comprehend or explain <a hard concept>b: having difficulty in doing something <hard of hearing>c: difficult to magnetize or demagnetize 11: being at once addictive and gravely detrimental to health <such hard drugs as heroin> 12: resistant to biodegradation <hard detergents><hard pesticides such as DDT> 13: being, schooled in, or using the methods of the natural sciences and especially of the physical sciences <a hard scientist> 14of money: contributed (as by individuals or political action committees) directly to a particular candidate or campaign
synonymshard, difficult, arduous mean demanding great exertion or effort. hard implies the opposite of all that is easy <farming is hard work>. difficult implies the presence of obstacles to be surmounted or puzzles to be resolved and suggests the need of skill or courage <the difficult ascent of the mountain>. arduous stresses the need of laborious and persevering exertion <the arduous task of rebuilding>.