Guacamole is an avocado-based relish or dip from the time of the Aztecs. In addition to avocados, the basic ingredients are lime juice and salt. Variations often include onion, tomato, hot chile peppers, garlic, cilantro, and other spices. Some American versions include ground black pepper corns or milk. It is often eaten with tortilla chips, although it can be spooned onto or into almost any savory Mexican dish. The name guacamole comes from Mexican Spanish via Nahuatl AhuacamOlli, from Ahuacatl (="avocado") + mOlli (="sauce").

Wherever avocados are expensive, guacamole is considered a delicacy. Sour cream or mayonnaise is sometimes mixed in as a filler, but such preparations are often considered inferior because they dilute and mask the flavor of the avocado. This is an American adaptation. [citation needed] Mexicans sometimes refer to diluted guacamole often served in low-cost taquerías as "aguamole," a portmanteau of Spanish "agua" ("water") and guacamole.

A traditional method of preparing guacamole involves the use of a molcajete (a Mexican mortar and pestle) to grind and mix the ingredients. In Texas and other areas of the southwest United States it is common to make guacamole as a quick party food or to bring it to a potluck luncheon by mashing ripe avocados with a favourite salsa using a fork. This quickly and easily adds the needed acid and salt.

Guacamole is popular in the United States as a snack food, especially around holidays and other major celebrations. Cinco de Mayo, Fourth of July, Super Bowl Sunday, and Easter each account for around 5% of annual avocado sales. Guacomole is also an increasingly popular party food in Australia and New Zealand.