Definitions
1.nounA person or thing that is acting or capable of acting.
2.nounAny component that is not passive. See Passivity (engineering).
3.adjectiveHaving the power or quality of acting; causing change; communicating action or motion; acting;—opposed to passive, that receives."certain active principles"
4.adjectiveQuick in physical movement; of an agile and vigorous body; nimble."an active child or animal"
5.adjectiveIn action; actually proceeding; working; in force"active hostilities"
6.adjectiveGiven to action; constantly engaged in action; energetic; diligent; busy"active mind"
7.adjectiveRequiring or implying action or exertion"active employment or service"
8.adjectiveGiven to action rather than contemplation; practical; operative"an active rather than a speculative statesman"
9.adjectiveBrisk; lively."an active demand for corn"
10.adjectiveImplying or producing rapid action."an active disease"
11.adjective(heading, grammar) About verbs.
12.adjective(of source code) Eligible to be processed by a compiler or interpreter.
13.adjectiveNot passive.
14.adjective(gay sexual slang) (of a homosexual man) enjoying a role in anal sex in which he penetrates, rather than being penetrated by his partner.