i tried to find an english name for this fruit, known as a camias (kamyas, kamias)--pronounced kahmyás--but couldn't. a relative of the carambola, it is believed to have originated in sri lanka, but it is cultivated and grows wild throughout southeast asia. the latin name for the tree itself is averrhoa bilimbi, but it is the carambola that is known in the philippines as the bilimbing, in malaysia as the belimbing, and on guam as the bilimbines. the tree, in english, is called a tropical cucumber tree, but the fruit is not considered a tropical cucumber. meh. whatever.
the camias is similar in texture and taste to the carambola, but its high oxalic acid content often makes it too acidic or sour to eat raw, although it is often used as a component in a raw salsa. it is made into pickles, preserves and candies, or added to curries or to soups as a souring agent. when i am loathe to leave the house, i go out to our tree and chop up a large quantity of fruit, sautée it with onions and garlic, and serve it with grilled or broiled salmon. the acids reduce dramatically in cooking, and it mellows out to a nice lemony pear flavour. excellent.
camias are so acidic, they are used to clean the blades of daggers, bleach stains off of skin, or take the tarnish off of brass (cheap oxy clean, anyone?) . the leaves are boiled for a cough remedy, and a flower infusion is said to be effective against fever and er, thrush.