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citron

American  
[si-truhn] / ˈsɪ trən /

noun

  1. a pale-yellow fruit resembling the lemon but larger and with thicker rind, borne by a small tree or large bush, Citrus medica, allied to the lemon and lime.

  2. the tree itself.

  3. the rind of the fruit, candied and preserved.

  4. a grayish-green yellow color.

  5. citron melon.


adjective

  1. having the color citron.

citron British  
/ ˈsɪtrən /

noun

  1. a small Asian rutaceous tree, Citrus medica, having lemon-like fruit with a thick aromatic rind See also citron wood

  2. the fruit of this tree

  3. Also called: citron melon.  a variety of watermelon, Citrullus vulgaris citroides, that has an inedible fruit with a hard rind

  4. the rind of either of these fruits, candied and used for decoration and flavouring of foods

  5. a greenish-yellow colour

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of citron

1375–1425; late Middle English < Middle French < Italian citrone < Latin citr ( us ) citrus + Italian -one augmentative suffix