abstract, bumpy, coarse, concept, conceptual, desert, dune, erosion, esoteric, existence, fanciful, flow, flowing, form, gentle, horizon, idea, image, imaginary, imagination, impression, irregular, landscape, layers, lines, material, nature, notched, peace, peaceful, perceive, perception, ragged, rough, sand, shadow, soft, softness, stepped, still, subjective, tactile, textural, textured, thought, tranquil, tranquility, undulating, undulation, windblown