The Collaborative International Dictionary of English v.0.48:

Hex- \Hex-\, Hexa \Hex"a\ [Gr. "e`x six. See Six.]
   A prefix or combining form, used to denote six, sixth, etc.;
   as, hexatomic, hexabasic.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hex
    adj 1: of or pertaining to a number system having 16 as its base
           [syn: hexadecimal, hex]
    n 1: an evil spell; "a witch put a curse on his whole family";
         "he put the whammy on me" [syn: hex, jinx, curse,
         whammy]
    v 1: cast a spell over someone or something; put a hex on
         someone or something [syn: hex, bewitch, glamour,
         witch, enchant, jinx]

Moby Thesaurus II by Grady Ward, 1.0:

118 Moby Thesaurus words for "hex":
   Jonah, Weird Sisters, abuse, accurse, afflict, aggrieve, anathema,
   anathematize, bad influence, ban, bedevil, befoul, bewitch,
   blaspheme, blasphemy, blast, blight, bring bad luck, cantrip,
   charm, commination, condemn, confound, corrupt, coven, crucify,
   curse, damage, damn, damnation, darn, defile, demonize,
   denunciation, deprave, despoil, destroy, diabolize, disadvantage,
   disserve, distress, do a mischief, do evil, do ill, do wrong,
   do wrong by, doom, enchant, enchantment, enchantress, envenom,
   evil eye, evil genius, evil star, excommunicate, excommunication,
   execrate, execration, exorcism, fulminate against, fulmination,
   get into trouble, glamour, hag, harass, harm, hoodoo, hurt,
   ill wind, impair, imprecate, imprecation, infect, injure, jinx,
   lamia, magic spell, malevolent influence, malison, malocchio,
   maltreat, menace, mistreat, molest, obsess, outrage, overlook,
   persecute, play havoc with, play hob with, poison, pollute,
   possess, prejudice, proscription, savage, scathe, shamaness,
   sorceress, spell, taint, threaten, throw a whammy, thunder against,
   thundering, torment, torture, violate, voodoo, wanga, weird,
   whammy, witch, witchwife, witchwoman, wound, wreak havoc on,
   wrong



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

hex
 n.

    1. Short for hexadecimal, base 16.

    2. A 6-pack of anything (compare quad, sense 2). Neither usage has
    anything to do with magic or black art, though the pun is appreciated
    and occasionally used by hackers. True story: As a joke, some hackers once
    offered some surplus ICs for sale to be worn as protective amulets against
    hostile magic. The chips were, of course, hex inverters.


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

hex

   1. hexadecimal.

   2. A 6-pack of anything (compare quad).  Neither usage has
   anything to do with magic or black art, though the pun is
   appreciated and occasionally used by hackers.  True story: As
   a joke, some hackers once offered some surplus ICs for sale to
   be worn as protective amulets against hostile magic.  The
   chips were, of course, hex inverters.

   3.  The hash character, used to introduce
   hexadecimal constants in some assembly languages.

   [Jargon File]

   (1995-03-06)