14th century, in the meaning defined above

1548, in the meaning defined at sense 1

borrowed from New Latin, genus name, going back to Latin chrȳsanthemon, chrȳsanthemum "a yellow-flowered composite plant," borrowed from Greek chrȳsánthemon "any of various plants with bright yellow flowers," from chrȳsós "gold" + ánthemon "blossom, flower" — more at chryso-, anthemion

1887, in the meaning defined at sense 1

1781, in the meaning defined above

borrowed from New Latin, going back to Late Latin, "the citron tree Citrus medica," going back to Latin, "the North African conifer Tetraclinis articulata," borrowed from or akin to Greek kédros "cedar, juniper" — more at cedar

NOTE: The word citrus in reference to a citrus tree is apparently not firmly attested before post-classical Latin. However, Pliny, who in Historia naturalis 13.29-31 discusses the North African conifer in some detail, adds that others use the word citrus for a different tree whose fruit is cursed by some for its odor and bitter taste, but sought out by others ("Alia est arbor eodem nomine, malum ferens execratum aliquis odore et amaritudine, aliis expetitum …"). This could well have been Citrus medica (literally, "Median citrus"). Compare also mālum citreum, "fruit of the citrus tree," alluded to by Scribonius Largus and Martial. It is unclear why a word for Tetraclinis articulata would have been extended to a tree as different as Citrus medica; similar uses of the wood, as for detering moths, have been suggested. An extensive discussion of the use of citrus wood in antiquity is in Russell Meiggs, Trees and Timber in the Ancient Mediterranean World (Oxford, 1982), pp. 286-92.

14th century, in the meaning defined above

1548, in the meaning defined at sense 1

borrowed from New Latin, genus name, going back to Latin chrȳsanthemon, chrȳsanthemum "a yellow-flowered composite plant," borrowed from Greek chrȳsánthemon "any of various plants with bright yellow flowers," from chrȳsós "gold" + ánthemon "blossom, flower" — more at chryso-, anthemion

1887, in the meaning defined at sense 1

1781, in the meaning defined above

borrowed from New Latin, going back to Late Latin, "the citron tree Citrus medica," going back to Latin, "the North African conifer Tetraclinis articulata," borrowed from or akin to Greek kédros "cedar, juniper" — more at cedar

NOTE: The word citrus in reference to a citrus tree is apparently not firmly attested before post-classical Latin. However, Pliny, who in Historia naturalis 13.29-31 discusses the North African conifer in some detail, adds that others use the word citrus for a different tree whose fruit is cursed by some for its odor and bitter taste, but sought out by others ("Alia est arbor eodem nomine, malum ferens execratum aliquis odore et amaritudine, aliis expetitum …"). This could well have been Citrus medica (literally, "Median citrus"). Compare also mālum citreum, "fruit of the citrus tree," alluded to by Scribonius Largus and Martial. It is unclear why a word for Tetraclinis articulata would have been extended to a tree as different as Citrus medica; similar uses of the wood, as for detering moths, have been suggested. An extensive discussion of the use of citrus wood in antiquity is in Russell Meiggs, Trees and Timber in the Ancient Mediterranean World (Oxford, 1982), pp. 286-92.