Where does the word "Tico" come from?

Costa Ricans often use the diminutive form of words to sound friendlier. They use, "ico", instead the more common "ito" diminutive expression in Spanish. For example, the word “momento” (moment), becomes “momentico” (little moment).This form of diminutive is rarely used in other Spanish speaking countries, so they started calling Costa Ricans "ticos".