Green’s Dictionary of Slang

shucks! excl.

also great shucks! I’ll be shucked! shuckles!
[shucks n. (2)]

(orig. US) a mild excl. of surprise, regret, annoyance etc.

[US]G.W. Harris ‘The Knob Dance’ Spirit of the Times (N.Y.) XV July in Inge (1967) 49: Oh, Shucks! give us ‘Rocky Mounting’.
[US]J.M. Field Drama in Pokerville 68: And Mr. Bagley was there with five more barrels, to do the same [i.e. to shoot] any gentleman who might say ‘shucks!’.
Buffalo Wkly Exp. (NY) 4 May 1/4: ‘Great shucks! What a spitfire!’.
[US]C.E. Craddock In the Tennessee Mountains 67: ‘Shucks!’ rejoined Pete incredulously.
[US]Helena Indep. (MT) 27 Dec. 1/5: ‘Shucks!’ said Jim-Polk, ‘wait till Harbert there gets stirred up’.
[UK] ‘’Arry in ’Arrygate’ (Second Letter) Punch 15 Oct. 169/3: Shucks! she’s as ’orty and stiff as you please.
[US]Flynt & Walton Powers That Prey 77: I’ll chance another; make or break; win or bust. The old woman ’ll dress me down, but shucks!—hard words don’t lower the price o’ eggs.
[UK]Marvel 2 Feb. 46: Shucks! No!
[US]T. McNamara Us Boys 20 July [synd. cartoon strip] Aw shuckles, it’s no use!
[US]H.L. Wilson Somewhere in Red Gap 72: If they didn’t fall for each other now – Shucks! They had to.
[US] ‘Whale Song’ J.J. Niles Singing Soldiers (1927) 11: ’Cause the whale he bucked and Jonah ducked / And the whale said well I will be shucked.
[US]N. Putnam West Broadway 188: ‘Shucks,’ says I.
[US]K. Nicholson Barker II ii: Well, shucks, I don’t know’s I could be a lawyer.
[US]E. Caldwell Tobacco Road (1958) 73: ‘Shucks,’ he said. ‘I couldn’t do that.’.
[UK]Edie Rutherford 1 Jan. diary in Garfield Our Hidden Lives (2004) 162: And now all these New Year’s honours. Shucks. Makes us tired.
[US]R. Prather Always Leave ’Em Dying 46: Shucks, don’t go formal on me, boy.
[US]N. Heard Howard Street 128: Shucks, I was whorin’ for two whole months before I dug I was a whore – bona fide.
[US]Ed Bullins ‘Dandy’ in King Black Short Story Anthol. (1972) 83: Shucks, she’s been out thare makin’ eyes at Junior Kane.
Dandy and Beano The Golden Years II n.p.: You asked for it! And shucks, now you’re gonna get it!
Dandy Comic Library No. 210 22: Shucks! Who’s the lucky gal?
[Aus]L. Redhead Peepshow [ebook] ‘You’ve become a bit of a celebrity around town.’ [...] ‘Shucks,’ I said.
[SA]Mail & Guardian (Johannesburg) 14 Jan. 🌐 ‘Shucks’ [...] is now pronounced ‘Shaiks’, as in ‘Shaiks! where did he go?’.

In exclamations

aw shucks!

1. a mild excl. denoting one’s feeling of emotion (usu. thanks but also agreement, denial etc), underpinned by (mild) embarrassment or apology.

H. Castelmon Snagged & Sunk 354: ‘Aw! Shucks!’ exclaimed Matt.
[US]Scribner’s Mag. July-Dec. 249/1: Aw shucks! you done made me fo’git it!
Religious Telescope 74 24: ‘Lucy Bell [...] Y’ ain’t techt the linin’ once.’ ‘Aw shucks’.
[US]Boys’ Life July 40/3: It’s this way— ah — er— I mean — Aw, shucks, I can’t express it the way I want to.
[US]Boys’ Life Oct. 21/1: ‘Aw shucks!’ says Grunter. ’If I wasn't tied up I'd bat you in the eye for that’.
[UK]Rover 13 Jan. 41: ‘Aw, Shucks!’ grinned Bandy.
[US]W. Burroughs Naked Lunch (1968) 122: Aw, shucks, fellers, tweren’t nothing.
[Aus]M. Bail Homesickness (1999) 202: ‘Aw, shucks,’ he mumbled.
[UK]Guardian Weekend 26 Feb. 3: Aw, shucks, ma’am.

2. attrib. use of sense 1.

[US](con. 1949) G. Pelecanos Big Blowdown (1999) 163: Florek gave an aw-shucks grin. ‘Her name is Kay.’.
[US]L. Stringer Grand Central Winter (1999) 82: Reggie screws a hasty aw-shucks grin in place. ‘I was only kidding,’ he says.
[US](con. 1964–8) J. Ellroy Cold Six Thousand 519: Wayne Senior smirked. Wayne Senior grinned aw-shucks.
[US]Courier Jrnl (Louisville, KY) 30 Mar, PA6/5: He was such an aw-shucks, down-to-earth, colorfil person.
[US]S. King Finders Keepers (2016) 51: Morris produced his best aw-shucks smile, ‘How you doin, Mrs Muller?’.