quad·rate (kwod´rāt) adj. roughly square in shape, or in cross-section. [ME < L quadrat- made square]

qua·mo·cli·di·on (kwä´mō kli´dē on) n. any plant of a subgenus of the largely South American genus Mirabilis L. subg. Quamoclidion (Choisy) Jeps. (of the Nyctaginaceae), now much-cultivated for its colourful flowers. [? < Gk. kuamos κύαμος bean + klitus κλιτῦς hillside]

quick·set (kwik´set´) n. Brit. 1 a slip or cutting, especially of hawthorn, which is planted to form part of a hedge. 2 such slips collectively. 3 a hedge derived from such slips. —adj. formed of, or derived from, such slips. [ME]

quill (kwil) v. of any leaflike or thalloid tissue, curling back or rolling back upon itself to form a cylindrical or tubular structure. [ME < MLG quiele]

quin·qui·fid (kwin´kwə fid´) adj. split about midway into five lobes; pentafid. [< L quinque five (comb.form.) + fid-, base of findere cleave]

quin·sy-wort (kwin´zē wôrt´) n. a small herb native to Europe and Asia Minor (Asperula cynanchica L., of the Rubiaceae), bearing opposite linear leaves with interpetiolar stipules so that they appear whorls of 4 (2 being larger), racemes of small whitish-pink flowers, and whose roots yield a red dye. [formerly valued as a medical remedy for quinsy or peritonsillar abscess]