The Collaborative International Dictionary of English v.0.48:

Summer \Sum"mer\, n. [OE. sumer, somer, AS. sumor, sumer; akin
   to OFries. sumur, D. zomer, OS. sumar, G. sommer, OHG. &
   Icel. sumar, Dan. sommer, Sw. sommar, W. haf, Zend hama, Skr.
   sam[=a] year. [root]292.]
   The season of the year in which the sun shines most directly
   upon any region; the warmest period of the year.
   [1913 Webster]

   Note: North of the equator summer is popularly taken to
         include the months of June, July, and August.
         Astronomically it may be considered, in the northern
         hemisphere, to begin with the summer solstice, about
         June 21st, and to end with the autumnal equinox, about
         September 22d.
         [1913 Webster]

   Indian summer, in North America, a period of warm weather
      late in autumn, usually characterized by a clear sky, and
      by a hazy or smoky appearance of the atmosphere,
      especially near the horizon. The name is derived probably
      from the custom of the Indians of using this time in
      preparation for winter by laying in stores of food.

   Saint Martin's summer. See under Saint.

   Summer bird (Zool.), the wryneck. [Prov. Eng.]

   Summer colt, the undulating state of the air near the
      surface of the ground when heated. [Eng.]

   Summer complaint (Med.), a popular term for any diarrheal
      disorder occurring in summer, especially when produced by
      heat and indigestion.

   Summer coot (Zool.), the American gallinule. [Local, U.S.]


   Summer cypress (Bot.), an annual plant (Kochia Scoparia)
      of the Goosefoot family. It has narrow, ciliate, crowded
      leaves, and is sometimes seen in gardens.

   Summer duck. (Zool.)
   (a) The wood duck.
   (b) The garganey, or summer teal. See Illust. of Wood duck,
       under Wood.

   Summer fallow, land uncropped and plowed, etc., during the
      summer, in order to pulverize the soil and kill the weeds.


   Summer rash (Med.), prickly heat. See under Prickly.

   Summer sheldrake (Zool.), the hooded merganser. [Local,
      U.S.]

   Summer snipe. (Zool.)
   (a) The dunlin.
   (b) The common European sandpiper.
   (c) The green sandpiper.

   Summer tanager (Zool.), a singing bird (Piranga rubra)
      native of the Middle and Southern United States. The male
      is deep red, the female is yellowish olive above and
      yellow beneath. Called also summer redbird.

   Summer teal (Zool.), the blue-winged teal. [Local, U.S.]

   Summer wheat, wheat that is sown in the spring, and matures
      during the summer following. See Spring wheat.

   Summer yellowbird. (Zool.) See Yellowbird.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Summer \Sum"mer\, n. [From Sum, v.]
   One who sums; one who casts up an account.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Summer \Sum"mer\, n. [F. sommier a rafter, the same word as
   sommier a beast of burden. See Sumpter.] (Arch.)
   A large stone or beam placed horizontally on columns, piers,
   posts, or the like, serving for various uses. Specifically:
   (a) The lintel of a door or window.
   (b) The commencement of a cross vault.
   (c) A central floor timber, as a girder, or a piece reaching
       from a wall to a girder. Called also summertree.
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Summer \Sum"mer\, v. i. [imp. & p. p. Summered; p. pr. & vb.
   n. Summering.]
   To pass the summer; to spend the warm season; as, to summer
   in Switzerland.
   [1913 Webster]

         The fowls shall summer upon them.        --Isa. xviii.
                                                  6.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Summer \Sum"mer\, v. t.
   To keep or carry through the summer; to feed during the
   summer; as, to summer stock.
   [1913 Webster]

WordNet (r) 3.0 (2006):

summer
    n 1: the warmest season of the year; in the northern hemisphere
         it extends from the summer solstice to the autumnal
         equinox; "they spent a lazy summer at the shore" [syn:
         summer, summertime]
    2: the period of finest development, happiness, or beauty; "the
       golden summer of his life"
    v 1: spend the summer; "We summered in Kashmir"

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "summer":
   aestival, arctic, autumn, autumnal, boreal, broiling sun, brumal,
   buy time, canicular, canicular days, consume time, dog days,
   equinoctial, fair weather, good old summertime, growing season,
   heat wave, hibernal, hiemal, high summer, hot wave, hot weather,
   humid weather, keep time, kill time, look for time, measure time,
   midday sun, midsummer, midwinter, muggy weather, occupy time,
   out of season, pass time, put in time, race against time, seasonal,
   solstitial, spend time, spring, springlike, stuffy weather,
   sultry weather, summerlike, summerly, summertide, summertime,
   summery, sunshiny weather, take time, take up time, use time,
   vernal, vertical rays, warm weather, weekend, winter, winterlike,
   wintery, wintry, work against time



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

SUMMER

   String manipulation and pattern matching language by Klint &
   Sint at CWI in the late 1970s.  It was recently used as the
   input and implementation language for the Dataflow Compiler
   Project at CWI.

   ["An Overview of the SUMMER Programming Language", Paul Klint,
   7th POPL, ACM 1980, pp. 47-55].