carambola

1. An ornamental evergreen tree (Averrhoa carambola), native to southeast Asia and having crisp, edible, yellow to orange, longitudinally ridged fruits that are star-shaped in cross section.
2. The fruit of this plant. Also called star fruit.

[Portuguese, perhaps from Marathi karambal.]

Or star fruit, long (8-12 cm) ribbed fruit of Averrhoa carambola and A. bilimbi; a 50-g portion is a rich source of vitamin C.

[kehr-ahm-BOH-lah] When cut crosswise, this showy fruit has a striking star shape, which is why it's also called star fruit. It favors tropical climates and thrives in the Caribbean countries, Hawaii, Central and South America and parts of Asia. The carambola ranges from 3 to 5 inches long and is easy to identify by the five definitive ribs that traverse its length. Its thin skin is a glossy golden-yellow, its matching flesh beautifully translucent and dotted occasionally with a dark seed. When ripe, the carambola is exceedingly juicy and fragrant. Its flavor, depending on the variety, can range from exotically sweet to refreshingly tart. In general, the broader set the ribs, the sweeter the fruit. Carambolas are available from summer's end to midwinter. Choose firm fruit that has a bright, even color. Those with greening on the ribs may be ripened at room temperature. Use ripe carambolas within a few days or store, wrapped tightly in a plastic bag, in the refrigerator for up to a week. Carambolas, which do not require peeling, are delicious eaten out of hand, or used in salads, desserts or as a garnish.

The noun has 2 meanings:

Meaning #1: East Indian tree bearing deeply ridged yellow-brown fruit
  Synonyms: carambola tree, Averrhoa carambola

Meaning #2: deeply ridged yellow-brown tropical fruit; used raw as a vegetable or in salad or when fully ripe as a dessert
  Synonym: star fruit