A word has an established meaning, but that meaning may have intelligible components and necessary concomitants. This gives three modes of indication.
Muṭābaqah (correspondence): The word indicates its full assigned meaning.
Taḍammun (inclusion): The word indicates a component within that meaning.
Iltizām (implication): The word indicates something external to its assigned meaning yet necessarily connected with it.
Mawḍūʿ lah means the whole meaning for which a word was assigned. Identifying it is essential: only then can one judge whether the indicated matter is the whole, an internal part, or an external concomitant.