Cross

From Reuters Financial Glossary

In the US, a cross is where the broker acts for both the buyer and seller of a security in the same deal. This is also known as an agency cross or dual agency, or in the UK it is known as a put through. Cross can also refer to a practice, usually illegal, where the buy and sell orders for a stock are offset by a broker without being recorded as a trade on the exchange. The risk is that either the buyer or the seller will not receive the fair market price.