Heard Christopher briefly angry — a pattern (10)

I believe the answer is:

crisscross

'a pattern' is the definition.
(crisscross is a kind of pattern)

'heard christopher briefly angry' is the wordplay.
I cannot really see how this works, but
'angry' could be 'cross' (I've seen this before) and 'cross' is found within the answer.
This explanation may well be incorrect...

(Another definition for crisscross that I've seen is " American game".)

I've seen this clue in The Times.

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