Offen (Ger.)
Open.
Offertory, Offertorio (It.), Offertoire (Fr.) (of-fer-twar), Offertorium (Ger. and Lat.). (I) The collection of the alms of the congregation during the communion service. (2) The anthem or motet sung by the choir at this time. (3) A piece of organ music performed during this time.