 The counterpart of significatio, the formal constituent of every meaning, is the word’s capacity to “stand for” different things (even though its significatio remains the same), depending on the context in which it is used. In the early stages of the development of the theory on the properties of terms, this feature of a word was called appellatio. For instance, the words ‘man’ and ‘horse’ can be used to stand for different individual men or horses. But they can also stand for themselves, e.g., when they are used in sentences such as ‘man is a noun’, or ‘horse is a noun’. Moreover, their meaning can differ according as the words are used in combination with verbs of different tenses.