a loud shout or other demonstration of welcome, goodwill, or approval.

act of acclaiming.

Liturgy . a brief responsive chant in antiphonal singing.

Ecclesiastical . response ( def. 3a ) . ?

by acclamation, by an oral vote, often unanimous, expressing approval by shouts, hand-clapping, etc.

rather than by formal ballot.

adjective

approbatory , commendatory , congratulatory , laudatory