crossword. cross word

Cross word or cross word ( two words ) means an irritable or angry ( cross ) unit of language with a distinct meaning ( word )--
He has such a cheerful disposition; he never says a cross word.
Hold your tongue; one cross word leads to another.

Crossword or crossword ( one word ) means or describes a kind of puzzle in which words fit together across and down, solved by clues given for each--
The game works like a crossword; you have to find a word that will fit into the other words.
He's doing the crossword puzzle; he won't pay any attention to you.

Now that you know that, you can say--
"If you don't want to hear a cross word, don't interrupt him while he's doing a crossword."