"word" or "words"?

[Iwanna]

Here is a quote:

"I suspected there would be a good-sized crowd, once word got out about my hanging," George Bush joked yesterday at the unveiling of his official portrait in Washington.

What is meaning of the highlighted expression?
Why not "words"，"a word" or "the word" here? I have been taught that an article would always be used in such a context.

[Happytofita]

I cannot tell you anything for sure because I am not a teacher. But you can expect everything from George Bush.
Bushism

[Alan]

Hi

'Once word got out' is the usual expression and it means: Once it became known or Once people knew.

Alan
_________________
English as a Second Language
You can read my ESL story Present Simple

[Iwanna]

Many thanks to Alan. I just feel puzzled. English language imposes so many rules on our foreign learners, but you native speakers always break these rules in many many ways. That is the biggest difficulty to me, for my mother tongue, Chinese, has a extremely simple grammatical system.