In order for you to read the entries for adjectives in the dictionary, or even look them up effectively, you need to know what are the “parts” dictionaries list for adjectives. There are two groups of adjectives: first/second declension adjectives and third declension adjectives.

Dictionaries list first/second declension adjectives by giving you the nominative singular for each of the three genders. The entry for the word bonus, for example, is bonus, -a, -um. Compare this to the chart for bonus in TABLE 6-2 and you will see that the dictionary entry represents the nominative singular masculine, feminine, and neuter in that order: bonus, bona, bonum, just like the first row of the chart.

The dictionary listings for third declension adjectives are trickier because third declension adjectives fall into three sub-groups. We will discuss them separately.