What is heavy? What is heavy? Having relatively great weight: a heavy load. Having relatively high density; having a high specific gravity.Large, as in number or quantity: a heavy turnout; heavy casualties. Large in yield or output: heavy rainfall. Of great intensity: heavy activity; heavy fighting. Having great power or force: a heavy punch. Violent; rough: heavy seas. Equipped with massive armaments and weapons: a heavy cruiser; heavy infantry. Large enough to fire powerful shells: heavy guns. Indulging to a great degree: a heavy drinker. Involved or participating on a large scale: a heavy investor. Of great import or seriousness; grave: heavy matters of state. Having considerable thickness: a heavy coat. Broad or coarse: drew the face with heavy lines. Dense; thick: a heavy fog. Slow to dissipate; strong: "There was a heavy fragrance of flowers and lemon trees” ( Mario Puzo). Too dense or rich to digest easily: a heavy dessert. Insufficiently leavened: heavy bread. Full of clay and readily saturated: heavy soil. Weighed down; burdened: trees heavy with plums. Emotionally weighed down; despondent: a heavy heart. Marked by or exhibiting weariness: heavy lids. Sad or painful: heavy news. Hard to do or accomplish; arduous: heavy going; heavy reading. Not easily borne; oppressive: heavy taxes.