Synonyms for Plenary:

adj.

complete (adjective)
done, total, comprehensive, solid, whole, accomplished, entire, intact, unsevered, exhaustive, sum, finished, universal, unified, collective, uncut, unabridged, all, conclusive, through, undivided, complete, thorough, full, integral, final.
entire (adjective)
inclusive, entire.
entire, whole (adjective)
inclusive, thorough, complete, full.

n.

pure, unadulterated, in depth, good, outright, utter, sound, resounding. inaugural, head-to-head, ceremonious, ceremonial, congressional, face to face, ritual, processional. lecturer, conveyor, voice, presenter, teller, speaker, orator.

Other synonyms:

processional, head-to-head, ceremonious, orator. congressional, ceremonial, face to face, inaugural, ritual, lecturer, conveyor. teller. speaker. voice. Other relevant words:
utter, resounding, head-to-head, congressional, inclusive, good, in depth, outright, pure, ceremonious, teller, lecturer, unadulterated, presenter, processional, orator, conveyor, voice, ritual, speaker, inaugural, sound, ceremonial.