An Etymological Dictionary of Astronomy and Astrophysics

To call together; summon to meet or assemble (Dictionary.com).

Etymology (EN): M.E., from M.Fr. convoquer, from L. convocare “to call together,” from → con- “together,” + vocare “to call,” from vox, → voice.

Etymology (PE): Hamvacidan, from ham-, → com-, + vac “word,” → voice, + -idan infinitive suffix.