available

adj. ready for use; attainable; unoccupied; valid

For the thermodynamic function availability, in the sense of available useful work, see exergy.For availability as a form of cognitive bias, see availability heuristic.In telecommunications and reliability theory, the term availability has the following meanings: 1. The degree to which a system, subsystem, or equipment is operable and in a committable state at the start of a mission, when the mission is called for at an unknown, i.e., a random, time. Simply put, availability is the proportion of time a system is in a functioning condition.
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Adjective
1. obtainable or accessible and ready for use or service; "kept a fire extinguisher available"; "much information is available through computers"; "available in many colors"; "the list of available candidates is unusually long"
(antonym) unavailable
(similar) accessible
(attribute) handiness, accessibility, availability, availableness
2. not busy; not otherwise committed; "he was not available for comment"; "he was available and willing to accompany her"
(synonym) uncommitted
(similar) free
3. convenient for use or disposal; "the house is available after July 1"; "2000 square feet of usable office space"
(synonym) usable, useable
(similar) disposable

(a.)
Such as one may avail one's self of; capable of being used for the accomplishment of a purpose; usable; profitable; advantageous; convertible into a resource; as, an available measure; an available candidate.
  

(a.)
Having sufficient power, force, or efficacy, for the object; effectual; valid; as, an available plea.
  

adjective
which can be got; the drug is available only on prescription; all available ambulances were rushed to the scene of the accident