TgO Ex19:13 :בְמִיגַד שוֹפָרָא אִנוּן מְרַשַן"מֻרשַן" לְמִסַק בְטוּרָא‏ : when the shofar blast is extended then they are permitted to go up the mountain †
See the entire entry for ršy#2 vb. to be in authority

TgO Ex19:13 :בְמִיגַד שוֹפָרָא‏ : at the extended sounding of the shofar
See the entire entry for šwpr n.m. shofar