What is "saddle oyster"

Saddle \Sad"dle\, n. [OE. sadel, AS. sadol; akin to D. zadel, G. sattel, OHG. satal, satul, Icel. s["o][eth]ull, Dan. & Sw. sadel; cf. Russ. siedlo; all perh. ultimately from the root of E. sit.]

1. A seat for a rider, -- usually made of leather, padded to span comfortably a horse's back, furnished with stirrups for the rider's feet to rest in, and fastened in place with a girth; also, a seat for the rider on a bicycle or tricycle.

2. A padded part of a harness which is worn on a horse's back, being fastened in place with a girth. It serves various purposes, as to keep the breeching in place, carry guides for the reins, etc.

3. A piece of meat containing a part of the backbone of an animal with the ribs on each side; as, a saddle of mutton, of venison, etc.

4. (Naut.) A block of wood, usually fastened to some spar, and shaped to receive the end of another spar.

5. (Mach.) A part, as a flange, which is hollowed out to fit upon a convex surface and serve as a means of attachment or support.

6. (Zo["o]l.) The clitellus of an earthworm.

7. (Arch.) The threshold of a door, when a separate piece from the floor or landing; -- so called because it spans and covers the joint between two floors.

8. (Phys. Geog.) A ridge connected two higher elevations; a low point in the crest line of a ridge; a col.

9. (Mining) A formation of gold-bearing quartz occurring along the crest of an anticlinal fold, esp. in Australia.

   Saddle bar (Arch.), one the small iron bars to which the lead panels of a glazed window are secured.
   --Oxf. Gloss.

   Saddle gall (Far.), a sore or gall upon a horse's back, made by the saddle.

   Saddle girth, a band passing round the body of a horse to hold the saddle in its place.

   saddle horse, a horse suitable or trained for riding with a saddle.

   Saddle joint, in sheet-metal roofing, a joint formed by bending up the edge of a sheet and folding it downward over the turned-up edge of the next sheet.

   Saddle roof, (Arch.), a roof having two gables and one ridge; -- said of such a roof when used in places where a different form is more common; as, a tower surmounted by a saddle roof. Called also saddleback roof.

   Saddle shell (Zo["o]l.), any thin plicated bivalve shell of the genera Placuna and Anomia; -- so called from its shape. Called also saddle oyster.

n. thin-shelled bivalve having the right valve deeply notched [syn: Anomia ephippium]