From ruwm; elevation, i.e. (adverbially) aloft -- on high.
see HEBREW ruwm
H7315. rom
רוֺם adverb on high, of direction (compare מָרוֺם 2) נָשָׂא יָדֵיהוּ רוֺם Habakkuk 3:10 (subject תְּהוֺם).