pro re nata
/(ˌ)prəʊ reɪ ˈnɑːtə/adverb
For an occasion as it arises; extempore, without prior provision; as required, as needed.
- Much used in the writing of medical prescriptions in the abbreviated form p. r. n..
adjective
Of a meeting, council, etc.: extraordinary, held or called to deal with a specific matter. Also more generally: resulting from or responding to particular circumstances.
Origin
Late 16th century. From classical Latin prō rē nātā in the circumstances, lit. ‘for the affair born’ from prō + rē, ablative of rēs thing, affair + nātā, ablative feminine of nātus born, past participle of nāscī to be born.