1. small opening of cavity.   stratum   orifice   projectile   phenomenon   Hint Half-n-half Clue   2. small outlet or inlet.   momentum   objective   vent   iota   Half-n-half Clue   3. marsh or soft and wet land.   suture   strut   trajectory   quagmire   Half-n-half Clue   4. universal remedy or cure-all.   miasma   increment   stratum   panacea   Half-n-half Clue   5. time when sun is farthest from the equator.   solstice   penumbra   iota   panacea   Half-n-half Clue   6. residue from smelting operation.   slag   symmetry   incline   matrix   Half-n-half Clue   7. optical illusion due to atmospheric conditions.   medium   mirage   repulsion   parasite   Half-n-half Clue