True. A broader definition is probably 'exploiting price differentials of correlated assets'.
Market is irrelevant, and both 'same item' and 'different but correlated items' are both subsets. And 'mispricing' presumes there's a true value, which may or may not be case.
My personal definitions are backwards from that: I just define `mispricing' as anything that allows arbitrage. (Especially risk-less arbitrage. But you can -- in theory -- make almost all arbitrage as risk-less as you want, with the right derivatives.)
Market is irrelevant, and both 'same item' and 'different but correlated items' are both subsets. And 'mispricing' presumes there's a true value, which may or may not be case.