The Collaborative International Dictionary of English v.0.48:

Iso- \I"so-\, Is- \Is-\ [Gr. 'i`sos equal.]
   A prefix or combining form, indicating identity, or equality;
   the same numerical value; as in isopod, isomorphous,
   isochromatic. Specif.:
   (a) (Chem.) Applied to certain compounds having the same
       composition but different properties; as in isocyanic.
   (b) (Organic Chem.) Applied to compounds of certain isomeric
       series in whose structure one carbon atom, at least, is
       connected with three other carbon atoms; -- contrasted
       with neo- and normal; as in isoparaffine; isopentane.
       [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

ISO
       International Standards Organisation [International Organization
for Standardization] (org.)


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

International Organization for Standardization
International Organisation for Standardisation
ISO

    (ISO) A voluntary, nontreaty organisation
   founded in 1946, responsible for creating international
   standards in many areas, including computers and
   communications.  Its members are the national standards
   organisations of 89 countries, including the American
   National Standards Institute.

   ISO produced the OSI seven layer model for network
   architecture.

   The term "ISO" is not actually an acronym for anything.  It is
   a pun on the Greek prefix "iso-", meaning "same".  Some ISO
   documents say ISO is not an acronym even though it is an
   anagram of the initials of the organisation's name.

   (http://iso.ch/).

   (1999-06-22)