Noun

1. Chemical agent capable of activity
2. The voice used to indicate that the grammatical subject of the verb is performing the action or causing the happening denoted by the verb
3. A person who is a participating member of an organization

Adjective

1. Tending to become more severe or wider in scope
2. Disposed to take action or effectuate change
3. Characterized by energetic activity
4. Exerting influence or producing a change or effect
5. Full of activity or engaged in continuous activity
6. (of the sun) characterized by an increased occurrence of sunspots and flares and radio emissions
7. Expressing that the subject of the sentence has the semantic function of actor:
8. (used of verbs (e.g. `to run') and participial adjectives (e.g. `running' in `running water')) expressing action rather than a state of being
9. (of e.g. volcanos) capable of erupting
10. (of e.g. volcanos) erupting or liable to erupt
11. Engaged in full-time work