1. hidden potential, not manifest.   saccharine   latent   metallurgical   porous   Hint Half-n-half Clue   2. motionless or unchanging.   stellar   opalescent   stagnant   somatic   Half-n-half Clue   3. suitable for drinking.   tertiary   potable   partial   saline   Half-n-half Clue   4. used as preventive for spread of disease.   volatile   prophylactic   unique   malleable   Half-n-half Clue   5. pertaining to earthquakes.   metallurgical   saline   seismic   refractory   Half-n-half Clue   6. shining and shedding light.   toxic   luminous   malleable   tactile   Half-n-half Clue   7. echoing or resounding.   resonant   valid   metallurgical   kinetic   Half-n-half Clue