A word appearing as G. polodrin “mighty” in the Gnomish Lexicon of the 1910s, an adjective form of G. polod “power, might, authority” (GL/64). It had an archaic variant {poldurin >>} †polurin or polorin which was sometimes used as a sobriquet for Tulcus.
Neo-Sindarin: Since ᴹ√POL(OD) still had to do with “strength” in Tolkien’s later writings, I’d adapt this word as ᴺS. polodhren “mighty, ✱powerful” for purposes of Neo-Sindarin using the later Sindarin adjective -ren. Given the meanings of its base noun (including authority), I’d assume this adjective has a connotation of political power. I’d constrast it with S. belaith which I’d use for “mighty” in general (independent of authority).
An adverb in the Gnomish Lexicon of the 1910s, a combination of G. go- “together” and G. mintha “in one place” (GL/41).