(uncountable) Conjugation is how a word changes based on several things. In English and European languages this word is usually a verb. It might change because of what time is talked about, who is talked about, or what part of the sentence the word is in.
I find German conjugation hard to remember.
Some linguists do not talk about conjugation because they think it is just an example of morphology.
(countable) A conjugation is the ways a word changes.
The conjugations of "to do" are "does," "did," and "doing."