The Collaborative International Dictionary of English v.0.48:

Mid \Mid\, n.
   Middle. [Obs.]
   [1913 Webster]

         About the mid of night come to my tent.  --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Mid \Mid\, prep.
   See Amid.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Mid \Mid\ (m[i^]d), a. [Compar. wanting; superl. Midmost.]
   [AS. midd; akin to OS. middi, D. mid (in comp.), OHG. mitti,
   Icel. mi[eth]r, Goth. midjis, L. medius, Gr. me`sos, Skr.
   madhya. [root]271. Cf. Amid, Middle, Midst, Mean,
   Mediate, Meridian, Mizzen, Moiety.]
   [1913 Webster]
   1. Denoting the middle part; as, in mid ocean.
      [1913 Webster]

            No more the mounting larks, while Daphne sings,
            Shall list'ning in mid air suspend their wings.
                                                  --Pope.
      [1913 Webster]

   2. Occupying a middle position; middle; as, the mid finger;
      the mid hour of night.
      [1913 Webster]

   3. (Phon.) Made with a somewhat elevated position of some
      certain part of the tongue, in relation to the palate;
      midway between the high and the low; -- said of certain
      vowel sounds; as, [=a] ([=a]le), [e^] ([e^]ll), [=o]
      ([=o]ld). See Guide to Pronunciation, [sect][sect] 10, 11.
      [1913 Webster]

   Note: Mid is much used as a prefix, or combining form,
         denoting the middle or middle part of a thing; as,
         mid-air, mid-channel, mid-age, midday, midland, etc.
         Also, specifically, in geometry, to denote a circle
         inscribed in a triangle (a midcircle), or relation to
         such a circle; as, mid-center, midradius.
         [1913 Webster]

WordNet (r) 3.0 (2006):

mid
    adj 1: used in combination to denote the middle; "midmorning";
           "midsummer"; "in mid-1958"; "a mid-June wedding"

Moby Thesaurus II by Grady Ward, 1.0:

126 Moby Thesaurus words for "mid":
   accented, alveolar, amid, amidships, amidst, among, amongst,
   apical, apico-alveolar, apico-dental, articulated, assimilated,
   average, back, barytone, between, betwixt, betwixt and between,
   bilabial, broad, cacuminal, center, centermost, central, cerebral,
   checked, close, consonant, consonantal, continuant, core, dental,
   dissimilated, dorsal, equatorial, equidistant, flat, front, glide,
   glossal, glottal, guttural, halfway, hard, heavy, high, interior,
   intermediary, intermediate, intonated, labial, labiodental,
   labiovelar, lateral, lax, light, lingual, liquid, low, mean,
   medial, median, mediocre, mediterranean, medium, mesial, mezzo,
   middle, middlemost, middling, midland, midmost, midships, midst,
   midway, monophthongal, muted, narrow, nasal, nasalized, nuclear,
   occlusive, open, over, oxytone, palatal, palatalized, pharyngeal,
   pharyngealized, phonemic, phonetic, phonic, pitch, pitched,
   posttonic, retroflex, rounded, semivowel, soft, sonant, stopped,
   stressed, strong, surd, syllabic, tense, thick, throaty,
   throughout, together with, tonal, tonic, twangy, unaccented,
   unrounded, unstressed, velar, vocalic, vocoid, voiced, voiceless,
   vowel, vowellike, weak, wide, with



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

MID
       Message IDentifier (ATM)


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

MID
       Mobile Information Device


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

MID
       Multiple Interface Declaration (OLSR)