Dictionary:

cilantro

  (sĭ-lăn'trō, -län'-)

See coriander (sense 1).

[Spanish, alteration of Late Latin coliandrum, from Latin coriandrum. See coriander.]

[sih-LAHN-troh; see-LAHN-troh] The bright green leaves and stems of the coriander plant. Cilantro (also called Chinese parsley and coriander) has a lively, pungent fragrance that some describe as "soapy." It is widely used in Asian, Caribbean and Latin American cooking and its distinctive flavor lends itself to highly spiced foods. Cilantro can be found year-round in most supermarkets and is generally sold in bunches. Choose leaves with a bright, even color and no sign of wilting. Cilantro may be stored for up to 1 week in a plastic bag in the refrigerator. Or place the bunch, stems down, in a glass of water and cover with a plastic bag, securing the bag to the glass with a rubber band. Refrigerate, changing water every 2 or 3 days. Just before using cilantro, wash and pat dry with paper towels. Both the leaves and relatively tender stems can be used in fresh or cooked dishes.

The noun has 2 meanings:

Meaning #1: Old World herb with aromatic leaves and seed resembling parsley
  Synonyms: coriander, coriander plant, Chinese parsley, Coriandrum sativum

Meaning #2: parsley-like herb used as seasoning or garnish
  Synonyms: coriander, Chinese parsley