[lebuffon]

You are correct, but in Forth for example, the colon is a word in the dictionary of words and so is semi-colon. They just happen to parse the input stream rather than taking arguments off the stack. Everything in Forth is called a "word".

So depending who your lawyer is, : and ; are "words". :=)

[ithkuil]

Yes. In forth some words have the "immediate" flag set. When such words are encountered during compilation they are executed nevertheless. This allows words such as ; to end a word definition and return to interpretation mode.

[ret2pop]

I am not generally knowledgeable about Forth and languages like it because the only experience I have writing in anything close to forth is in my own language. Thanks for explaining.