Synonyms for Convoke:

n.

study at call. cluster, round up, congregate, get together, group. send for, request.

v.

communication (verb)
convene.
convoke (verb)
assemble, muster, collect, convene, gather.
meet (verb)
assemble, request, convene, gather, muster.

Other synonyms:

congregate. cluster. congregate
assemble.
Other relevant words:
group, send for, congregate, request, cluster, get together.