From The Collaborative International Dictionary of English v.0.48:
Posterior \Pos*te"ri*or\ (p[o^]s*t[=e]"r[i^]*[~e]r), a. [L.
posterior, compar. of posterus coming after, from post after.
See Post-.]
1. Later in time; hence, later in the order of proceeding or
moving; coming after; -- opposed to prior.
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Hesiod was posterior to Homer. --Broome.
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2. Situated behind; hinder; -- opposed to anterior.
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3. (Anat.) At or toward the caudal extremity; caudal; -- in
human anatomy often used for dorsal.
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4. (Bot.) On the side next the axis of inflorescence; -- said
of an axillary flower. --Gray.
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