| AFFINE | Geometry of parallel lines |
| HERRINGBONE | Pattern consisting of columns of parallel lines, with all the lines in one column sloping one way and all the lines in the next column sloping the other (11) |
| BARCODE | Machine-readable code in the form of numbers and a pattern of parallel lines (7) |
| STATUARY | Pieces of sculpture mostly standing on a pair of parallel lines |
| STRIATION | A marking of parallel lines |
| CROSSHATCHING | Shading with intersecting sets of parallel lines (13) |
| GRID | Framework of parallel lines |
| CROSSHATCH | Mark with intersecting sets of parallel lines |
| BAR | Series of parallel lines and spaces that can be read by an optical scanner, ... code |
| EUCLID | Father of Geometry of ancient Greece |
| GEODETIC | Relating to the geometry of curved surfaces (8) |
| GEODESIC | Relating to the geometry of curved surfaces (8) |
| PLATO | Philosopher who said "Writing is the geometry of the soul" |
| HARMONY | A combination of simultaneously sounded musical notes producing an aesthetically agreeable sound; the art, science or study of chords; or, a collation of parallel narratives (7) |
| TWILL | Textile weave in which the weft yarns are worked around two or more warp yarns, creating a pattern of parallel diagonal lines (5) |
| NOTANOTHER | Name of theory originally left out of parallel universe in silence (3,7,4) |
| WORD | Name of theory originally left out of parallel universe in silence (3,7,4) |
| HARP | Plucked musical instrument consisting of a frame supporting a series of parallel strings (4) |
| BLOWBYBLOW | Detailed description of parallel bursts of wind (4-2-4) |
| UPC | Set of parallel bars, initially |