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1.
cross rock - verb (transitive)

To wear (or, euphemistically, to rock) two or more brands at the same time. In doing so, the wearer is "crossing" (mixing) their labels.

The standard conjugation of the idiomatic verb "to rock" apply.
"Hey, I like your Puma kicks, but why are you cross rockin' 'em with a Lacoste tee?"
by RoddickRemixed September 05, 2007