The word adjective comes from the Latin word adiectum which means to set next to or add. Adjectives are “set next to" nouns to modify them in character, size, color, etc.. In English, adjectives are usually found before nouns as in:
The big chair
The red balloon
The enigmatic child
In Latin, nouns usually come before adjectives in the sense that the noun is more important than its modifier. There are a few exceptions to this rule, especially when dealing with size, numbers, or demonstratives such as this, that, or those. Occasionally, a writer may want to call attention to an adjective than is normally necessary and put the adjective before the noun. Remember that unlike English, Latin word order is far less important because Latin is an inflected language.
Adjectives in a Latin dictionary are normally listed alphabetically by the masculine nominative singular form when there is a discrepancy among the genders. Consider the following example:
Magnus –a –um great, large; of sound, loud; of value, high
Notice that unlike nouns, adjectives are not assigned a universal gender. The –a indicates that the feminine form of the adjective is magna in the nominative singular and the –um tells that the neuter form is magnum. From there, the adjective declines just as if it were a noun: magnus, magni, magno, etc.; magna, magnae, magnae, etc., and magnum, magni, magno, etc..
Latin adjectives can function as the subject, direct object, indirect object, etc, just like a noun, when the noun the adjective normally would modify is missing. For example:
Magnus in agro est. (The great man is in the field)
Magna in agro est. (The great woman is in the field)
Magnum in agro est. (The great thing is in the field)
The remainder of the dictionary entry indicates the different ways a Latin adjective can be translated under a variety of circumstances. In the case of magnus –a –um, great or large is the most likely translation unless it modifies a noun that has to do with sound. In that case, the adjective should be translated as loud. Similarly, with nouns denoting value, high should be used as in a high price.
One difficultly with Latin adjectives is agreement with nouns that have a gender different than that which is expected within a declension. For example, the first declension is normally associated with feminine nouns and yet some first declension nouns are actually masculine. For example, poeta (poet) is a masculine, first-declension noun. Therefore, any adjective that modifies it must agree with it in gender, number, and case but not necessarily form. For example:
Poeta magnus in agro est. (The great poet is in the field)
Notice that the adjective magnus is in its masculine form to coincide with the masculine noun poeta. Consequently, it is necessary to memorize the genders of all nouns so that there is no confusion when using adjectives to modify nouns. This can save many trips to the Latin dictionary just to discover a word’s gender.