וְכ֥וֹס פַּרְעֹ֖ה בְּיָדִ֑י וָאֶקַּ֣ח אֶת־הָֽעֲנָבִ֗ים וָֽאֶשְׂחַ֤ט אֹתָם֙ אֶל־כּ֣וֹס פַּרְעֹ֔ה וָאֶתֵּ֥ן אֶת־הַכּ֖וֹס עַל־כַּ֥ף פַּרְעֹֽה׃
and Pharaoh’s cup was in my hand; and I took the grapes, and pressed them into Pharaoh’s cup, and I gave the cup into Pharaoh’s hand.’
Rashi on Genesis
ואשחט translate it as the Targum AND I PRESSED — The word occurs frequently in the Mishna (but only here in the Bible).
Radak on Genesis
וכוס...ואשחט, the word שחט signals closing something off. It occurs also in this sense in Shabbat 143 אין שוחטים את הפירות, that it is forbidden to squeeze the juice out of fruit on the Sabbath.