1. impermeable   uncertain or not fixed   impervious or unpassable.   large or extensive like the heavenly bodies.   confirmed or recurring as a disease.   Hint Half-n-half Clue   2. aseptic   surgically sterile or preventing infection.   spread around like a gas; verbose.   uncertain or not fixed   having indigestion.   Half-n-half Clue   3. empirical   based on experiment, not theory.   next to or adjoining.   practicable or possible.   imbalanced or not similar about dividing line.   Half-n-half Clue   4. impervious   not able to penetrate or understand.   impenetrable or unpassable.   having common center.   tending to a center.   Half-n-half Clue   5. chronic   confirmed or recurring as a disease.   dangerous or risky.   of exterior curvature or bulging outwards.   practicable or possible.   Half-n-half Clue   6. acrid   of the day or daily.   causing compression or contraction.   sharply pungent.   periodic shedding (of leaves).   Half-n-half Clue   7. herbivorous   next to or adjoining.   implied but not expressed.   herb-eating or vegetarian.   basic or essential.   Half-n-half Clue