1. convex   pertaining to the back (of an animal).   periodic shedding (of leaves).   having common center.   of exterior curvature or bulging outwards.   Hint Half-n-half Clue   2. cerebral   pertaining to the brain.   flesh-eating.   sharply pungent.   of motive force or energetic.   Half-n-half Clue   3. empirical   based on experiment, not theory.   pertaining to the back (of an animal).   flesh-eating.   heat-liberating.   Half-n-half Clue   4. elliptical   inferred by reasoning; derived as conclusions.   shaped like an oval; ambiguous or baffling.   basic or essential.   not able to penetrate or understand.   Half-n-half Clue   5. ductile   theoretical and not concrete.   grinding down or rubbing off.   fragrant or sweet-smelling.   capable of being drawn into wire or flexible.   Half-n-half Clue   6. astronomical   cold like ice.   large or extensive like the heavenly bodies.   shaped like an oval; ambiguous or baffling.   fragrant or sweet-smelling.   Half-n-half Clue   7. infinitesimal   infinitely small or very tiny.   opposite or inverted in relation or order.   grinding down or rubbing off.   corresponding or in harmony.   Half-n-half Clue