active
/ˈak-tiv/
adjective
characterized by action rather than by contemplation or speculation
producing or involving action or movement
asserting that the person or thing represented by the grammatical subject performs the action represented by the verb
an active life
noun
an active person : one engaged in an action or activity
fraternity alumni and actives
noun
usually long-lasting immunity that is acquired through production of antibodies within the organism in response to the presence of antigens