Fetching details from the dictionary...

crossing (shares); matched cross trade
Note: stock trading term
「売買」 has another reading with different meanings.
引け前に同一銘柄の売買が成立した。
A cross trade in the same stock was executed before the close.
その注文は場内で売買として処理された。
That order was processed as a cross trade on the exchange.
売買に当たるかどうかを監理部門が確認した。
The compliance team checked whether it counted as a cross trade.