The crossword solution for the term 'Word of Action' is VERB, which is a four-letter word. A verb is a part of speech that expresses an action, occurrence, or state of being. Verbs are used to describe how an action is performed, how something exists, or how something appears. Verbs can also be used to express feelings, desires, and opinions. Verbs are essential to forming complete sentences and are often used in conjunction with other parts of speech such as nouns, adjectives, and adverbs.