‖ pyrethrum
(paɪˈrɛθrəm, -ˈiːθrəm)
Also 6–7 (from Fr.) pyrethre.
[L. pyrethrum, -on (Pliny) = sense 1, a. Gr. πύρεθρον feverfew: cf. πυρετός fever. In F. pyrèthre, in OF. piretre (13th c. in Hatz.-Darm.). Cf. pelleter, pellitory.]
1. Originally, The name of the plant Anacyclus Pyrethrum, N.O. Compositæ, also called Pellitory of Spain, a native of Barbary, Arabia, and Syria, having a pungent root (radix pyrethri) used in medicine. Now so called only in pharmacy.
| 1562 Turner Herbal ii. 107 b, Pyrethrum..hath a stalk & leues like vnto fenell. 1578 Lyte Dodoens iii. xix. 342 The roote of Pyrethre is hoate and dry in the thirde degree. 1583 Rates of Customs D vij, Piretheum [sic] the pounde iii d. 1607 Topsell Four-f. Beasts 350 To provoke him to neese, by blowing Pepper and Pyrethre beaten to powder, up into his nostrils. 1799 G. Smith Laboratory II. 422 Take pyrethrum (wild or bastard pellitory) boil it in strong vinegar, so as to prevent the steam from having any vent. 1858 Mayne Expos. Lex., Pyrethrum, The pharmacopœial name for the root of the plant Anthemis pyrethrum, or..Anacyclus pyrethrum, or pellitory of Spain. |
2. a. [Adopted as a generic name in A. Haller Enumeratio Methodica Stirpium Helvetiæ (1742) II. 720.] A composite plant of the genus formerly so called, now included in the genus Chrysanthemum or the subgenus Tanacetum.
As a current florists' name, usually applied to Pyrethrum (or Chrysanthemum) roseum, now grown in many colours, single and double, in summer-gardens in England; also to P. parthenifolium aureum, a free-growing hardy dwarf annual or biennial, extensively used for carpet-bedding and edging, having white flowers with yellow disks. Both species are natives of the Caucasus, Armenia, and Persia, and were introduced into England c 1803.
| 1882 Garden 13 May 322/3 There seems to be a growing taste for single-flowered Pyrethrums. 1907 Outlook 9 Nov. 596/1 New sorts..which combine the virtues of the pyrethrum and daisy with the peculiar quality of the chrysanthemum. 1939 A. Cumming Hardy Chrysanthemums ii. 27 Efforts of the writer to cross this species with the garden chrysanthemum have been unsuccessful, which may indicate..that it is a true pyrethrum. 1951 Dict. Gardening (R. Hort. Soc.) I. 469/1 The forms [of chrysanthemum] most widely grown are varieties of C. morifolium..and of C. roseum, generally known in gardens as Pyrethrums. 1964 G. B. Schaller Year of Gorilla (1965) iv. 86 Many Europeans have settled in the rift mountains. There they grow tea and white-flowered pyrethrum, used in making insect powder. 1976 Hortus Third (L. H. Bailey Hortorium) 267/1 Feverfews. These are forms of C[hrysanthemum] Parthenium, sometimes known as pyrethrum. Ibid., Pyrethrums. These are derived from C. coccineum, and bloom in late spring and summer. |
b. In full, pyrethrum powder: an insecticide made of the powdered flower-heads of Chrysanthemum (or Tanacetum) cinerariifolium or C. coccineum.
| 1876 Duhring Dis. Skin 599 The best preventives against bugs in beds are corrosive sublimate [and] pyrethrum powder. 1888 Insect Life I. 145 Pyrethrum powder was freely used. 1902 Chambers's Jrnl. 22 Feb. 191/1 A house where a case of fever had occurred would be fumigated with burning pyrethrum, contiguous dwellings being treated in the same manner. [1905 Westm. Gaz. 15 Apr. 2/3 Another product [of Montenegro] is the ‘pyrethrum’ flower, which is dried and exported to Italy..for use as insect-powder.] 1955 Sci. News Let. 10 Sept. 169/2 Pyrethrum is harmless to human beings and animals, but fatal to flies. 1964 Which? Apr. 115/1 The risk is reduced by using..short-lived insecticides, such as derris or pyrethrum. 1978 C. Jeffrey in V. H. Heywood Flowering Plants of World 268/3 Tanacetum cinerariifolium is the main commercial source of natural pyrethrum, used as an insecticide. |