The Collaborative International Dictionary of English v.0.48:

Rear \Rear\, v. t. [imp. & p. p. Reared (r[=e]rd); p. pr. &
   vb. n. Rearing.] [AS. r[=ae]ran to raise, rear, elevate,
   for r[=ae]san, causative of r[imac]san to rise. See Rise,
   and cf. Raise.]
   1. To raise; to lift up; to cause to rise, become erect,
      etc.; to elevate; as, to rear a monolith.
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            In adoration at his feet I fell
            Submiss; he reared me.                --Milton.
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            It reareth our hearts from vain thoughts. --Barrow.
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            Mine [shall be] the first hand to rear her banner.
                                                  --Ld. Lytton.
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   2. To erect by building; to set up; to construct; as, to rear
      defenses or houses; to rear one government on the ruins of
      another.
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            One reared a font of stone.           --Tennyson.
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   3. To lift and take up. [Obs. or R.]
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            And having her from Trompart lightly reared,
            Upon his courser set the lovely load. --Spenser.
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   4. To bring up to maturity, as young; to educate; to
      instruct; to foster; as, to rear offspring.
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            He wants a father to protect his youth,
            And rear him up to virtue.            --Southern.
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   5. To breed and raise; as, to rear cattle.
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   6. To rouse; to stir up. [Obs.]
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            And seeks the tusky boar to rear.     --Dryden.
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   Syn: To lift; elevate; erect; raise; build; establish. See
        the Note under Raise, 3
      (c) .
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WordNet (r) 3.0 (2006):

rearing
    adj 1: rearing on left hind leg with forelegs elevated and head
           usually in profile; "a lion rampant" [syn: rampant(ip),
           rearing]
    n 1: the properties acquired as a consequence of the way you
         were treated as a child [syn: raising, rearing,
         nurture]
    2: helping someone grow up to be an accepted member of the
       community; "they debated whether nature or nurture was more
       important" [syn: breeding, bringing up, fostering,
       fosterage, nurture, raising, rearing, upbringing]

Moby Thesaurus II by Grady Ward, 1.0:

100 Moby Thesaurus words for "rearing":
   anabatic, apotheosis, apprenticeship, ascendant, ascending,
   ascensional, ascensive, ascent, assumption, basic training,
   beatification, bolt upright, breaking, breeding, canonization,
   climbing, conditioning, cultivation, deification, development,
   discipline, downright, drill, drilling, elevation, enshrinement,
   erect, erecting, erection, escalation, exaltation, exercise,
   fetching-up, fostering, green thumb, grooming, growing, heaving up,
   height, housebreaking, improvement, in the ascendant,
   in-service training, leaping, lifting, lofting, manual training,
   military training, mounting, nurture, nurturing,
   on-the-job training, practice, preparation, raising, rampant,
   readying, rehearsal, rising, saltatory, scandent, scansorial,
   skyrocketing, sloyd, spiraling, springing, stand-up,
   standing on end, standing up, sursum corda, training, uparching,
   upbringing, upbuoying, upcast, upcoming, upended, upgoing, upgrade,
   upheaval, uphill, uphillward, uplift, uplifting, upping, upraised,
   upraising, upreared, uprearing, upright, uprising, upsloping,
   upstanding, upthrow, upthrust, upward, upwith, vertical,
   vocational education, vocational training