Exodus 2:16

ולכהן מדין THE PRIEST OF MIDIAN — כהן signifies the chief amongst them (see Targ. Onkelos and Mekhilta יתרו); he had abandoned the idol-worship to which they were addicted and they banished him, driving him away from them (Exodus Rabbah 1:32). את הרהטים THE GUTTERS — the troughs for the currents of water which are excavated in the ground.

וּלְכֹהֵ֥ן מִדְיָ֖ן שֶׁ֣בַע בָּנ֑וֹת וַתָּבֹ֣אנָה וַתִּדְלֶ֗נָה וַתְּמַלֶּ֙אנָה֙ אֶת־הָ֣רְהָטִ֔ים לְהַשְׁק֖וֹת צֹ֥אן אֲבִיהֶֽן׃

Now the priest of Midyan had seven daughters: and they came and drew water, and filled the troughs to water their father’s flock.