The Collaborative International Dictionary of English v.0.48:

Volatile \Vol"a*tile\, a. [F. volatil, L. volatilis, fr. volare
   to fly, perhaps akin to velox swift, E. velocity. Cf.
   Volley.]
   1. Passing through the air on wings, or by the buoyant force
      of the atmosphere; flying; having the power to fly. [Obs.]
      [1913 Webster]

   2. Capable of wasting away, or of easily passing into the
      aeriform state; subject to evaporation.
      [1913 Webster]

   Note: Substances which affect the smell with pungent or
         fragrant odors, as musk, hartshorn, and essential oils,
         are called volatile substances, because they waste away
         on exposure to the atmosphere. Alcohol and ether are
         called volatile liquids for a similar reason, and
         because they easily pass into the state of vapor on the
         application of heat. On the contrary, gold is a fixed
         substance, because it does not suffer waste, even when
         exposed to the heat of a furnace; and oils are called
         fixed when they do not evaporate on simple exposure to
         the atmosphere.
         [1913 Webster]

   3. Fig.: Light-hearted; easily affected by circumstances;
      airy; lively; hence, changeable; fickle; as, a volatile
      temper.
      [1913 Webster]

            You are as giddy and volatile as ever. --Swift.
      [1913 Webster]

   Volatile alkali. (Old Chem.) See under Alkali.

   Volatile liniment, a liniment composed of sweet oil and
      ammonia, so called from the readiness with which the
      latter evaporates.

   Volatile oils. (Chem.) See Essential oils, under
      Essential.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Volatile \Vol"a*tile\, n. [Cf. F. volatile.]
   A winged animal; wild fowl; game. [Obs.] --Chaucer. --Sir T.
   Browne.
   [1913 Webster] Volatileness

WordNet (r) 3.0 (2006):

volatile
    adj 1: evaporating readily at normal temperatures and pressures;
           "volatile oils"; "volatile solvents" [ant: nonvolatile,
           nonvolatilisable, nonvolatilizable]
    2: liable to lead to sudden change or violence; "an explosive
       issue"; "a volatile situation with troops and rioters eager
       for a confrontation" [syn: explosive, volatile]
    3: marked by erratic changeableness in affections or
       attachments; "fickle friends"; "a flirt's volatile
       affections" [syn: fickle, volatile]
    4: tending to vary often or widely; "volatile stocks"; "volatile
       emotions"
    n 1: a volatile substance; a substance that changes readily from
         solid or liquid to a vapor; "it was heated to evaporate the
         volatiles"

Moby Thesaurus II by Grady Ward, 1.0:

167 Moby Thesaurus words for "volatile":
   adrift, afloat, agitable, airy, alternating, amorphous,
   birdbrained, birdwitted, bouncy, brittle, bubbly, buoyant,
   capricious, changeable, changeful, charged, coquettish,
   corruptible, deciduous, desultory, deviable, dizzy, downy, dying,
   eccentric, edgy, effervescent, ephemeral, erratic, eruptive,
   ethereal, evanescent, evaporable, evaporative, expansive,
   explosive, faddish, fading, fast and loose, featherbrained,
   feathery, fickle, fitful, fleeting, flickering, flighty, flippant,
   flirtatious, flitting, fluctuating, fluffy, fly-by-night, flying,
   foamy, fragile, frail, freakish, frivolous, frothy, fugacious,
   fugitive, giddy, gossamery, hair-trigger, impermanent, impetuous,
   imponderous, impulsive, inconsistent, inconstant, indecisive,
   infirm, insubstantial, irregular, irresolute, irresponsible, leger,
   light, light as air, light-minded, lighter than vanity, lubricious,
   mazy, mercurial, momentary, moody, mortal, mousse, mutable,
   nondurable, nonpermanent, passing, perishable, protean,
   quicksilver, rambling, resilient, restless, roving, scatterbrained,
   sensitive, shallow, shallow-headed, shallow-minded, shallow-pated,
   shallow-witted, shapeless, shifting, shifty, short-lived,
   shuffling, skittery, skittish, souffle, spasmodic, spineless,
   startlish, superficial, temperamental, temporal, temporary, tense,
   ticklish, toying, transient, transitive, transitory, unaccountable,
   uncertain, uncontrolled, undependable, undisciplined, undurable,
   unenduring, unfixed, unheavy, unpredictable, unprofound,
   unreliable, unrestrained, unsettled, unstable, unstable as water,
   unstaid, unsteadfast, unsteady, vacillating, vagrant, vaporable,
   vaporescent, vaporizable, vaporizing, variable, versatile,
   vicissitudinary, vicissitudinous, volatilizable, wandering, wanton,
   wavering, wavery, wavy, wayward, weightless, whimsical,
   wishy-washy, yeasty



The Free On-line Dictionary of Computing (30 December 2018):

volatile

   1.  volatile variable.

   2.  See non-volatile storage.

   (1997-06-05)