Spinal

google

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late 16th century: from late Latin spinalis, from Latin spina (see spine).

wiktionary

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Borrowed from Late Latin spīnālis(“of or belonging to the spine”), from spīna(“a prickle, spine”) +‎ -ālis(“-al”, adjectival suffix). Equivalent to spine +‎ -al.

etymonline

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spinal (adj.)

1570s, from Late Latin spinalis "of or pertaining to a thorn or the spine," from Latin spina (see spine). Spinal tap recorded from 1960.