behind – сзади, позади

behind (adv.)
Old English behindan "behind, after," from bi "by" + hindan "from behind" (see hind (adj.)). The prepositional sense emerged in Old English. Euphemistic noun meaning "backside of a person" is from 1786. Phrase behind the times is from 1905. Behind the scenes (1711) is from the theater; figurative sense attested by 1779.

hind (adj.) (задний)
c.1300, "rear, back," perhaps a back-formation from Old English behindan "back, behind," used as adverb and preposition, or from or influenced by Old English hindan (adv.) "from behind," from Proto-Germanic *hind- "behind" (cognate with Gothic hindan (prep.) "on that side of, beyond, behind;" German hinten "behind"), of unknown origin. Possibly influenced by Middle English hiner (adv.) "back, rear."

Происхождение слова неизвестно. Не уверен.
Сзади, значит не видно, что-то спрятанное. Это опять русское слово «ховать» - прятать. ХОВАТЬ – ХВТ – замены «в» - «v» - «u» - «n» и «т» - «d». HVT – HN (n)T.