Boolean expression to logic gates
Usually, an operator that's written implicitly by just putting the operands next to each other (e.g., "$xy$" for $x\land y$ in logic or $x\times y$ in arithmetic) has precedence over binary operators that are written out explicitly (e.g., $\lor$ or&nbsp;$\oplus$ in logic, or $+$ in arithmetic). Indeed, any author who uses a different convention to that needs a good stern talking to.  But note that it is only a convention.

So the expression in the question means $(xy)\oplus z$, unless the person who wrote it hates us. This view is reinforced by the fact that logical and is multiplication modulo&nbsp;2, and xor is addition modulo&nbsp;2 and we'd expect multiplication to have precedence over addition.