Definition of "oh"

Oh baby, baby, how was I supposed to know / That something wasn't right here?

1998, Max Martin, ...Baby One More Time (song performed by Britney Spears)

And oh how stingingly acute, and pungently grievous and tormentive, are the remembrancing Reflections of a separate uncloathed Soul in the other World, upon a review of its mad Choice, foolish Hopes, fruitless Desires […]

1703, Lawrence Smith, The Evidence of Things Not Seen, page 143

Oh, by what plots, by what forswearings, betrayings, oppressions, imprisonments, tortures, poisonings, and under what reasons of state and politic subtilty, have these forenamed kings […] pulled the vengeance of God upon themselves […]

1614, Walter Ralegh [i.e., Walter Raleigh], The Historie of the World […], London: […] William Stansby for Walter Burre, […], (please specify |book=1 to 5)

"Oh! . . oh! . . I can't bear it . . It is too much . . I die . . I am going . ." were Polly's expressions of extasy

1749, [John Cleland], “(Please specify the letter or volume)”, in Memoirs of a Woman of Pleasure [Fanny Hill], London: […] G. Fenton [i.e., Fenton and Ralph Griffiths] […]

I'm off with the raggle-taggle gypsy-oh.

1968, MacKinlay Kantor, Beauty Beast

There were ohs and ahs, and the people twisted about as they looked for her. Then they began to applaud.

2011, Seabert Parsons, The Lost Codex of Palenque, page 240

A quarter of an hour elapsed, and then, after several rings at the door-bell, a smothered laugh, and a good deal of ohing and ahing, the door was thrown open, and one by one, as they were announced, in came the expected characters.

1852, Merry's museum and Parley's magazine, volumes 23-24, page 46

One genuine recycled local glass of aitch-two-oh

2006, Ben Bova, Titan, page 33

Exes and Ohs: A Downtown Girl's (Mostly Awkward) Tales of Love, Lust, Revenge, and a Little Facebook Stalking

2011, Shallon Lester, (Please provide the book title or journal name)