Definition of goody two shoes in US English:

goody two shoes

noun

  • An ostentatiously virtuous or well-behaved person.

    ‘she was such a goody two shoes’
    • ‘Dan's brother is such a goody two-shoes, he probably doesn't even know the meaning of the phrase ‘lying through your teeth’.’
    • ‘About the only thing Ashcroft is guilty of is being a goody two shoes.’
    • ‘His character goes in one scene from an insufferably noble goody two shoes to a mean spirited madman that's so cold blooded that he barely breaks a sweat in the sauna.’
    • ‘Being called a goody two-shoes seems to make her act more like one.’
    • ‘Archy is the fair country boy and an idealist, though he is not presented as a goody two shoes.’
    • ‘Her one stipulation is that any adverts she makes for the brand are not shown in the US or Britain so she can preserve her goody two-shoes, health conscious image in her main market.’
    • ‘Put yourself above bitchery at your peril; you'll become a goody two shoes, a smartarse.’
    • ‘Which is not to say 1940s and 1950s children were all goody two shoes.’
    • ‘But goody two-shoes me, ‘always’ listens to what her mother says.’
    • ‘‘No one likes a goody two shoes,’ her room-mate warns, and though she isn't actively dislikable her innocence strains credulity.’
    • ‘You want me to be some sweet little goody two-shoes who can't handle herself.’

Origin

Mid 18th-century: from the nickname of the heroine of History of Little Goody Two-shoes (1766), a popular children's story in which an orphan girl triumphs over adversity through her unwavering virtue and hard work to become a teacher and marry a rich man, using her newfound wealth to help the poor and do good works.