The Collaborative International Dictionary of English v.0.48:

Twink \Twink\ (tw[i^][ng]k), v. i. [OE. twinken. See Twinkle.]
   To twinkle. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Twink \Twink\ (tw[i^][ng]k), n.
   1. A wink; a twinkling. [Obs.]
      [1913 Webster]

   2. (Zool.) The chaffinch. [Prov. Eng.]
      [1913 Webster]

The Jargon File (version 4.4.7, 29 Dec 2003):

twink
 /twink/, n.

    1. [Berkeley] A clue-repellant user; the next step beyond a clueless one.

    2. [UCSC] A read-only user. Also reported on the Usenet group soc.motss;
    may derive from gay slang for a cute young thing with nothing upstairs
    (compare mainstream ?chick?).

    3. On MU* systems that specialize in role-playing, refers to behavior of a
    (usually inexperienced) player that either ignores rules or social
    convention, or disrupts the natural flow of a scene to show off super
    powers.

    We are informed that in Indian country, the term twink generally refers to
    blondes into generic ?Native American spirituality?. Signs include Indian
    jewelry with MADE IN THAILAND stamped on it, crystals, Clairol black hair,
    wearing swimsuits to powwows, Cherokee princess grandmas, a love of Dances
    with Wolves, and a fear of AIM and the NCAI. The twink nature is
    everywhere.


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

twink

   /twink/ [UCSC] Equivalent to read-only user.  Also reported
   on the Usenet group soc.motss; may derive from gay slang for
   a cute young thing with nothing upstairs (compare mainstream
   "chick").