The Collaborative International Dictionary of English v.0.48:

Stem \Stem\ (st[e^]m), n. [AS. stemn, stefn, staefn; akin to OS.
   stamn the stem of a ship, D. stam stem, steven stem of a
   ship, G. stamm stem, steven stem of a ship, Icel. stafn,
   stamn, stem of a ship, stofn, stomn, stem, Sw. stam a tree
   trunk, Dan. stamme. Cf. Staff, Stand.]
   1. The principal body of a tree, shrub, or plant, of any
      kind; the main stock; the part which supports the branches
      or the head or top.
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            After they are shot up thirty feet in length, they
            spread a very large top, having no bough nor twig in
            the trunk or the stem.                --Sir W.
                                                  Raleigh.
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            The lowering spring, with lavish rain,
            Beats down the slender stem and breaded grain.
                                                  --Dryden.
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   2. A little branch which connects a fruit, flower, or leaf
      with a main branch; a peduncle, pedicel, or petiole; as,
      the stem of an apple or a cherry.
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   3. The stock of a family; a race or generation of
      progenitors. "All that are of noble stem." --Milton.
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            While I do pray, learn here thy stem
            And true descent.                     --Herbert.
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   4. A branch of a family.
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            This is a stem
            Of that victorious stock.             --Shak.
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   5. (Naut.) A curved piece of timber to which the two sides of
      a ship are united at the fore end. The lower end of it is
      scarfed to the keel, and the bowsprit rests upon its upper
      end. Hence, the forward part of a vessel; the bow.
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   6. Fig.: An advanced or leading position; the lookout.
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            Wolsey sat at the stem more than twenty years.
                                                  --Fuller.
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   7. Anything resembling a stem or stalk; as, the stem of a
      tobacco pipe; the stem of a watch case, or that part to
      which the ring, by which it is suspended, is attached.
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   8. (Bot.) That part of a plant which bears leaves, or
      rudiments of leaves, whether rising above ground or wholly
      subterranean.
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   9. (Zool.)
      (a) The entire central axis of a feather.
      (b) The basal portion of the body of one of the
          Pennatulacea, or of a gorgonian.
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   10. (Mus.) The short perpendicular line added to the body of
       a note; the tail of a crotchet, quaver, semiquaver, etc.
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   11. (Gram.) The part of an inflected word which remains
       unchanged (except by euphonic variations) throughout a
       given inflection; theme; base.
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   From stem to stern (Naut.), from one end of the ship to the
      other, or through the whole length.

   Stem leaf (Bot.), a leaf growing from the stem of a plant,
      as contrasted with a basal or radical leaf.
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