The word "zesty" comes from the word "zest", which refers to the outer, colored part of a citrus fruit's peel. Zest is often added to recipes to enhance flavor. The word "zesty" is an
adjective that means
something is appealingly piquant or lively, or has a lot of flavor or spice.
For example, you might describe a lunch as zesty if it's highly flavored, or you might describe salsa as zesty if it's extra hot.