In linguistics and grammar, conjugation has two basic meanings. One meaning is the creation of derived forms of a verb from basic forms, or principal parts.
The second meaning of the word conjugation is a group of verbs which all have the same pattern of inflections. Thus all those Latin verbs which in the present tense have 1st singular -ō, 2nd singular -ās, and infinitive -āre are said to belong to the 1st conjugation, those with 1st singular -eō, 2nd singular -ēs and infinitive -ēre belong to the 2nd conjugation, and so on. The number of conjugations of regular verbs is usually said to be four.