saddletree

[sad-l-tree] /ˈsæd lˌtri/
noun
1.
the frame of a saddle.
Origin
1375-1425; late Middle English sadeltre. See saddle, tree
British Dictionary definitions for saddletree

saddletree

/ˈsædəlˌtriː/
noun
1.
the frame of a saddle