Brier

Noun

 * 1) A thorny Mediterranean shrub.
 * 2) A pipe made from the roots of that shrub.
 * 3) A metaphor for any unpleasantry in general.

Thesaurus
adherent, adhesive, barnacle, bramble, brier bush, bristle, bulldog, burr, bush, cactus, catchweed, cement, cleavers, decal, decalcomania, glue, goose grass, gunk, leech, limpet, molasses, mucilage, needle, nettle, paste, pine needle, plaster, prickle, quill, remora, scrub, shrub, shrubbery, spicule, spiculum, spike, spikelet, spine, sticker, syrup, thistle, thorn, yucca