graywacke

gray·wacke

noun \ˈgrā-ˌwak, -ˌwa-kə\

Definition of GRAYWACKE

: a coarse usually dark gray sandstone or fine-grained conglomerate composed of firmly cemented fragments (as of quartz or feldspar)

Origin of GRAYWACKE

partial translation of German Grauwacke

First Known Use: 1811

Rhymes with GRAYWACKE

aback, ack-ack, alack, amtrac, Anzac, arrack, attack, backpack, backtrack, Balzac, bareback, blackjack, blowback, bootblack, bootjack, brushback, bushwhack, buyback, callback, calpac, carjack, champac, cheapjack, coatrack, come back, comeback, cookshack, crackback, crookback, cut back, cutback, Dayak, dieback, Dirac, draw back, drawback, fall back, fallback, fastback, fast-track, fatback, feedback, finback, fireback, flapjack, flashback, fullback, gimcrack, giveback, greenback, gripsack, guaiac, halfback, half-track, hardback, hardhack, hardtack, hatchback, hayrack, haystack, hijack, hogback, hold back, holdback, hopsack, horseback, humpback, hunchback, Iraq, jam-pack, jet-black, Kanak, Karnak, kayak, Kazak, kickback, knapsack, knickknack, kulak, kyack, laid-back, lampblack, leaseback, linac, macaque, man jack, manpack, Micmac, mossback, muntjac, Muzak, notchback, offtrack, one-track, outback, packsack, payback, pitch-black, play back, playback, plow back, plowback, Prozac, pullback, quillback, racetrack, ransack, rickrack, roll back, rollback, roorback, rucksack, runback, sad sack, scatback, serac, set back, setback, shellac, shellback, shoeblack, shoepac, sidetrack, six-pack, skewback, skipjack, skyjack, slapjack, slotback, Slovak, smokejack, smokestack, snap back, snapback, snowpack, softback, sumac, swayback, sweepback, swept-back, switchback, tailback, tarmac, thornback, throw back, throwback, thumbtack, ticktack, tieback, tie tack, tombac, touchback, tow sack, trictrac, tripack, unpack, wetback, whaleback, wingback, wisecrack, wolf pack, woolpack, woolsack, yashmak, zwieback

graywacke

noun    (Concise Encyclopedia)

Sedimentary rock composed of sand-sized grains in a fine-grained clay matrix. The sand-sized grains frequently include rock fragments of wide-ranging mineralogies (e.g., pyroxenes, amphiboles, feldspars, and quartz). The clay matrix may constitute up to 50% of the volume. Of the clay minerals, chlorite and biotite are most abundant. The matrix tends to bind the grains strongly and form a relatively hard rock.

Variants of GRAYWACKE

graywacke or dirty sandstone