The Collaborative International Dictionary of English v.0.48:

Latex \La"tex\, n. [L.]
   1. (Bot.) A milky or colored juice in certain plants in
      cavities (called latex cells or latex tubes). It contains
      the peculiar principles of the plants, whether aromatic,
      bitter, or acid, and in many instances yields caoutchouc
      upon coagulation. The lattex of the India rubber plant
      produces the rubber of commerce on coagulation.
      [1913 Webster +PJC]

   2. (Chem.) Any aqueous emulsion of finely divided rubber or
      plastic particles, especially such an emulsion used as a
      base for paint; as, a latex paint.
      [PJC]

WordNet (r) 3.0 (2006):

latex
    n 1: a milky exudate from certain plants that coagulates on
         exposure to air
    2: a water-base paint that has a latex binder [syn: latex
       paint, latex, rubber-base paint]

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

LaTeX

    (Lamport TeX) Leslie Lamport
   's document preparation system built on
   top of TeX.  LaTeX was developed at SRI International's
   Computer Science Laboratory and was built to resemble
   Scribe.

   LaTeX adds commands to simplify typesetting and lets the user
   concentrate on the structure of the text rather than on
   formatting commands.

   BibTeX is a LaTeX package for bibliographic citations.

   Lamport's LaTeX book has an exemplary index listing every symbol,
   concept and example in the book.  The index in the, now obsolete,
   first edition includes (on page 221) the mysterious entry
   "Gilkerson, Ellen, 221".  The second edition (1994) has an entry
   for "infinite loop" instead.

   ["LaTeX, A Document Preparation System", Leslie Lamport, A-W
   1986, ISBN 0-201-15790-X (first edition, now obsolete)].

   (1997-11-17)