Side dishes that accompany alchoholic beverages. Almost any Korean dish may be served as anju
Some of these side dishes can also be ordered as an appetizer or a main dish. These side dishes are different from the banchan side dishes served with a regular Korean meal.
Some examples of anju are: fried chicken, dried squid with gochujang, assorted fruits, dubu kimchi (tofu with kimchi), or peanuts.
Source
Source: Hannaone’s Korean Food Dictionary / Wikipedia