The word is unique to this attestation (also cited in GDF and TL) and its precise meaning and etymology are unresolved. The current definition is based upon the Latin original, and, like GDF and TL do, translates the term oraculum. The DMLBS lists the rare word orationarius, which, formally, could have produced oreisonier in Anglo-Norman. The Latin term is an adjective, which, used elliptically, can mean ‘book of collects or prayers’. Finally, the word may also be interpreted as an infinitive, synonymous to orer1, but derived from the substantive oreison (although such a formation is not attested elsewhere and implies a freer and somewhat obscure translation of the Latin in Camb Ps).