Ruler of the Synagogue
RULER OF THE SYNAGOGUE (Heb. רֹאשׁ הַכְּנֶסֶת; Gr. ἀρχισυνάγωγος, G801, ruler of a synagogue). The ruler of the synagogue was the man chosen to care for the physical arrangements of the synagogue services. The president of the synagogue would be the equivalent designation today.
International Standard Bible Encyclopedia (1915)
See Ruler, 3, (1), (2).