1. unavoidable or bound to occur.   empirical   cognitive   discrete   inevitable   Hint Half-n-half Clue   2. inactive or lacking power of action.   astral   concurrent   inert   embryonic   Half-n-half Clue   3. that corrodes or burns; biting or sarcastic.   amorphous   carcinogenic   caustic   brackish   Half-n-half Clue   4. periodic shedding (of leaves).   deciduous   caustic   humid   eugenic   Half-n-half Clue   5. diverse or mixed.   abstract   heterogenous   cognitive   infinitesimal   Half-n-half Clue   6. improving race by selective breeding.   eugenic   chronic   ciliated   discrete   Half-n-half Clue   7. pertaining to the brain.   cosmic   cerebral   congruent   glacial   Half-n-half Clue