[{"Bold_text": "noun", "List Items": ["a sudden, forceful backward movement; recoil.", "a strong or violent reaction, as to some social or political change:a backlash of angry feeling among Southern conservatives within the party.", "Machinery.the space between the thickness of a gear tooth and the width of the space between teeth in the mating gear, designed to allow for a film of lubricant, binding from heat expansion and eccentricity, or manufacturing inaccuracies.play or lost motion between loosely fitting machine parts.", "the space between the thickness of a gear tooth and the width of the space between teeth in the mating gear, designed to allow for a film of lubricant, binding from heat expansion and eccentricity, or manufacturing inaccuracies.", "play or lost motion between loosely fitting machine parts.", "Angling.a snarled line on a reel, usually caused by a faulty cast."]}, {"Bold_text": "verb (used without object)", "List Items": ["to make or undergo a backlash."]}]