squawk

A shrill noise, especially made by a voice or bird. If made by a bird, it typically signals discomfort or anger; a yell, scream, or call.

Noun

A shrill noise, especially made by a voice or bird. If made by a bird, it typically signals discomfort or anger; a yell, scream, or call.
A four-digit transponder code used by aircraft for identification or transmission of emergency signals.
A complaint or objection.
- That was the last roundup for McCutcheon’s Cresswell; it never moved from that field again. Not that there was any squawk from the landlord; the two of them owned it, of course. - 1983, Stephen King, Uncle Otto's Truck:
An issue or complaint related to aircraft maintenance.
- We think instructors should stress the importance of writeups on all maintenance squawks after the completion of each flight. More important, something should be done by the aircraft operator to correct such squawks. -...
The American night heron.
A warning message indicating a possible error.
- The function-hiding code above, for instance, goes through a different (but widely used) compiler with nary a squawk. - 2012, Scott Meyers, Effective C++ Digital Collection: 140 Ways to Improve Your Programming:

First attested in 1821. Unknown, but probably of imitative origin (compare dialectal Italian squacco (“small-crested heron”) and English quack).

To make a squawking noise; to yell, scream, or call out shrilly.
- The hens woke up squawking with terror because they had all dreamed simultaneously of hearing a gun go off in the distance. - 1943 November – 1944 February (date written; published 1945 August 17), George Orwell...
To speak out; to protest.
To report an infraction; to rat on or tattle; to disclose a secret.
- "I'll slit your throat if you squawk on us," Krantz threatened. - 1948, Andrew Geer, The Sea Chase, page 68:
To produce a warning message, indicating a possible error.
- That way, if you type = instead of ==, the compiler will squawk because you can't assign something to a constant. - 1993, Steve Maguire, Writing Solid Code:
- You want the compiler to squawk if you try to instantiate for a type that doesn't implement IPrioritizable. - 2013, Bill Sempf, Chuck Sphar, Stephen R. Davis, C# 5.0 All-in-One For Dummies:
To set or transmit a four-digit transponder code. (Normally followed by the specific code in question.)
- After discovering that the hydraulic system is faulty, the pilots squawked 7700 and declared mayday.
To back out in a mean way.