trixe -rix-ti'e-trix- gismu

x₁ is posterior/behind/back/in the rear of x₂ which faces/in-frame-of-reference x₃.

Also: x₃ is the standard of orientation for x₂; spine (= rixybo'u, rixybo'ukamju). See also crane, rebla, mlana, pritu, zunle.

In notes:

bekpi: x₁ is the 'back', dorsum of body x₂
crane: x₁ is anterior/ahead/forward/(in/on) the front of x₂ which faces/in-frame-of-reference x₃.
denriku: x₁ is the alveolar ridge of x₂; (adjective) x₁ is alveolar.
denrikuti'e: x₁ is post-alveolar, behind the alveolar ridge of x₂
jmarixtendo: x₁ is the Achilles tendon of x₂
mlana: x₁ is to the side of/lateral to x₂ and facing x₃ from point of view/in-frame-of-reference x₄.
pritu: x₁ is to the right/right-hand side of x₂ which faces/in-frame-of-reference x₃.
rebla: x₁ is a/the tail/appendix [body-part] of x₂; [metaphor: trailing, following portion/appendage].
rixybakfu: t₁=b₁ contains b₂ wrapped with b₃ to be hauled on the back of t₂.
ti'ekla: k₁ withdraws to k₂ from origin k₃=t₂ via route k₄ using means/vehicle k₅.
vinti'e: x₁ is (in) the background of x₂ by frame of reference x₃
zunle: x₁ is to the left/left-hand side of x₂ which faces/in-frame-of-reference x₃.