It is actually spelled "jicama" but pronounced as you have spelled it. Jicama is a root vegetable sometimes called a Mexican potato. It looks similar to a large turnip or radish. It has brown papery skin which is peeled before eating. Jicama has white crisp flesh that may taste similar to a pear or apple. It can be eaten raw, and is a great addition to a veggie platter as it does not discolor when exposed to air, or cooked in a stir fry. When cooked it takes on the flavors it is cooked with.
Jicama is an excellent source of fiber with 6grams for one cup, and gives you 43% of your daily value of vitamin C. It is low in calories with only 49 calories for one cup.