Definition of loony tunes in English:

loony tunes

(also looney tunes)

adjective

North american
informal
  • Crazy; deranged.

    ‘it sounds a little loony tunes’
    • ‘The whole deal was loony tunes - except without wackiness or daffiness.’
    • ‘‘Claims to have the world's most dangerous variety trick,’ is the line she uses to open the song, seemingly oblivious to the degree of danger her own loony tunes variety act carries.’
    • ‘If you run through the policies now, they sound totally loony tunes.’
    • ‘With Sun, Uranus, Neptune and the weekend Moon playing loony tunes in the curious universe of Aquarius, who could predict what this week's winds of mischief will bring?’
    • ‘But the convenience of centralised shopping doesn't have to mean the insanity of centralised livestock farming and loony tunes imports of things we don't need and didn't ask for.’

plural noun

North american
informal
  • Crazy or deranged people.

    ‘funny thing about your family: the first generation are all loony tunes’
    • ‘But looking at the rest of his features, you would never know that he is a looney tunes.’
    • ‘The first question is why parents should be happy to entrust their children to the bunch of looney tunes who run our schools.’
    • ‘Everyone said, "You guys are a bunch of looney tunes." Now, they're saying, "You're a bunch of geniuses…."’

Origin

1980s: from Looney Tunes, the name of a US animated cartoon series that began in the 1930s, featuring Bugs Bunny and other characters.