In a dictionary, if the word being searched for is a conjugation of its stem, the dictionary often shows the definition for the stem instead of the conjugation. If the word is not a conjugation, the stem is often found in the word origin or its related forms.
A word stem is generally the root or origin of the word. Sometimes a stem is the base word from which other conjugations and forms are derived. For example, the word "wait" is the stem of the words "waiter," "waited" and "waiting." When searching for the definition of "waited" on Dictionary.com, the user is directed to the definition for "wait," instead. "Waited" is simply the stem word conjugated into past tense; therefore, the meaning is the same.
Another example of a stem is a Latin term that appears in several different words. For example, the words "potentate," "potentiate" and "potential" all originate from the Latin term for "power." On Dictionary.com, the word "potent" or "potency" appears in the origin section of the definitions for all three words. Thus, a reader can see that these words are related by the common stem, "potent."
The stem of a word also helps determine its definition. Words containing the stem "potent" generally pertain to the concept of "power" in some way. Using the dictionary to find the definition of the stem can help with understanding a word.