Ouch
natural exclamation: first recorded in English in the mid 17th century.
wiktionary
Uncertain. Some sources say the interjection is attested since 1838 [1] (and specifically in American English) and derives ultimately from German autsch, [2] [3] perhaps specifically via Pennsylvania German outch(“cry of pain”), as early attestations of the interjection are from Pennsylvania. [3] However, others say the interjection is a "mere" [4] or "natural" exclamation attested since the mid 1600s, [5] and the 1933 OED [3] cites one instance of a verb "ouch" in 1654, "Sancho Pancas Runs Ouching round the mountaine like a ranck-Asse". [6]
Variant forms.
etymonline
ouch (interj.)
exclamation expressing pain, 1837, from Pennsylvania German outch, cry of pain, from German autsch. The Japanese word is itai. Latin used au, hau.
