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keel

The keel of a boat is the beam that runs the length of the hull — the body of the boat — and can extend vertically into the water to provide stability.

A keel doesn't just refer to the stabilization of boats. When you're on "an even keel," you're stable and steady. On a bird, the keel (or breastbone) enables a bird to fly. On the other hand, if you keel over, you're quite the opposite, since you've just gone crashing to the floor.

Definitions of keel
  1. noun
    one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability
    see moresee less
    types:
    bilge keel
    either of two lengthwise fins attached along the outside of a ship's bilge; reduces rolling
    type of:
    beam
    long thick piece of wood or metal or concrete, etc., used in construction
  2. noun
    the median ridge on the breastbone of birds that fly
    see moresee less
    type of:
    carina
    any of various keel-shaped structures or ridges such as that on the breastbone of a bird or that formed by the fused petals of a pea blossom
  3. noun
    a projection or ridge that suggests a keel
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    type of:
    projection
    any solid convex shape that juts out from something
  4. verb
    walk as if unable to control one's movements
    synonyms: careen, lurch, reel, stagger, swag
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    type of:
    walk
    use one's feet to advance; advance by steps
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