"of or pertaining to the metatarsus," 1739, from metatarsus "middle bones of the foot" (early 15c.), from Medieval Latin metatarsus, from meta "between, next after" (see meta-) + tarsus (see tarsus (n.)). As a noun, "a metatarsal bone," by 1854.
word-forming element of Greek origin meaning 1. "after, behind; among, between," 2. "changed, altered," 3. "higher, beyond;" from Greek meta (prep.) "in the midst of; in common with; by means of; between; in pursuit or quest of; after, next after, behind," in compounds most often meaning "change" of place, condition, etc. This is from PIE *me- "in the middle" (source also of German mit, Gothic miþ, Old English mið "with, together with, among"). Notion of "changing places with" probably led to senses "change of place, order, or nature," which was a principal meaning of the Greek word when used as a prefix (but also denoting "community, participation; in common with; pursuing").
The third sense, "higher than, transcending, overarching, dealing with the most fundamental matters of," is due to misinterpretation of metaphysics (q.v.) as "science of that which transcends the physical." This has led to a prodigious erroneous extension in modern usage, with meta- affixed to the names of other sciences and disciplines, especially in the academic jargon of literary criticism: Metalanguage(1936) "a language which supplies terms for the analysis of an 'object' language;" metalinguistics (by 1949); metahistory (1957), metacommunication, etc.
the ankle bones collectively, 1670s, Modern Latin, from Greek tarsos "ankle, sole of the foot, rim of the eyelid," originally "flat surface, especially for drying," from PIE root *ters- "to dry." The connecting notion is the bones of the "flat" of the foot (Greek tarsos podos).
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit tarsayati "dries up;" Avestan tarshu- "dry, solid;" Greek teresesthai "to become or be dry," tersainein "to make dry;" Latin torrere "dry up, parch," terra "earth, land;" Gothic þaursus "dry, barren," Old High German thurri, German dürr, Old English þyrre "dry;" Old English þurstig "thirsty."
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Definitions of metatarsal from WordNet
any bone of the foot between the ankle and the toes;