How Well Do You Know English Slang?
1821, probably of imitative origin (cf. dialectal Italian squacco "small crested heron"). The noun is attested from 1850. Squawk-box "loud-speaker" is from 1945.
: Okay, what's your squawk this morning? (1909+)
[echoic of an unpleasant sound, esp the grating screech of a bird]