1. with only one color.   valid   saline   schematic   monochromatic   Hint Half-n-half Clue   2. marked with ridges or parallel grooves on surface.   striated   tactile   permeable   stagnant   Half-n-half Clue   3. allowing light to pass freely; clearly apparent.   porous   ligneous   transparent   kinetic   Half-n-half Clue   4. opalescent or displaying rainbow-like colors.   sidereal   synthetic   oblique   iridescent   Half-n-half Clue   5. shining and shedding light.   obtuse   viscous   precipitate   luminous   Half-n-half Clue   6. small enough or unimportant as to be neglected.   obtuse   nocturnal   temporal   negligible   Half-n-half Clue   7. of many forms.   multiform   soluble   rarefied   oblique   Half-n-half Clue