It is the plural of papyrus, which is an early writing material (paper) that was made from the stems of reeds (plants that grow in marshy areas).
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Papyri was a type of paper made out of "Papyrus" stems (which grow in tropical water). This was the a common medium on which ancient egyptians and hebrews used to write their texts. The "Dead Sea Scrolls" were ancient papyri on which some of the oldest copies of some of The Bible text have been found.
papyri
Henry George Meecham has written: 'Light from ancient letters' -- subject(s): Accessible book, Criticism, interpretation, Biblical Greek language, Oxyrhynchus papyri, Bible 'Light from ancient letters: private correspondence in the non-literary papyri of Oxyrhynchus of the first four centuries' -- subject(s): Antiquities, Bible, Biblical Greek language, Criticism, interpretation, Greek letters, History and criticism, Language, style, Manuscripts, Greek (Papyri), Oxyrhynchus papyri
Joseph Gilbert Manning has written: 'The Hauswaldt papyri' -- subject(s): Demotic Papyri, Egyptian language, History, Papyri, Demotic, Sources
papyri
Bernard Pyne Grenfell has written: 'New classical fragments and other Greek and Latin papyri' -- subject(s): Manuscripts, Greek (Papyri), Manuscripts, Latin (Papyri) 'New Sayings of Jesus and Fragment of a Lost Gospel from Oxyrhyncus' 'Hellenica oxyrhynchia cum Theopompi et Cratippi fragmentis recognoverunt brevique adnotatione critica' -- subject(s): Hellenica oxyrhynchia 'Greek papyri' 'Oxyrhynchus Papyri (Graeco-Roman Memorial)' 'Fayum Towns and Their Papyri (Graeco-Roman Memorial)' 'The Hibeh Papyri (Graeco-Roman Memoirs)'
The plural of papyrus is papyri or papyruses. Both are acceptable, but papyri is preferred.
Edgar Lobel has written: 'The Oxyrhynchus Papyri (Graeco-Roman Memorial)' 'Racine' 'Oxyrhynchus Papyri 37 (Graeco-Roman Memoirs)' 'Oxyrhynchus Papyri 30 (Graeco-Roman Memoirs)' 'A Greek historical drama' -- subject(s): Antiquities, Facsimiles, Greek Historical drama, Greek drama, Greek drama (Tragedy), Historical drama, Greek, History and criticism, Manuscripts, Manuscripts, Greek (Papyri), Oxyrhynchus papyri
David Stewart Crawford has written: 'Fuad I University papyri' -- subject(s): Manuscripts, Greek (Papyri) 'Papyri Michaelidae' -- subject(s): Bibliography, Manuscripts, Greek (Papyri), Manuscripts, Latin (Papyri), Ostraka
Hans-Udo Rosenbaum has written: 'Repertorium Der Griechischen Christlichen Papyri II: Kirchenvater-Papyri'
The Bible is silent in regards the age of Stephen when he was stoned.
Kathleen McNamee has written: 'Abbreviations in Greek literary papyri and ostraca' -- subject(s): Glossaries, vocabularies, Greek Abbreviations, Greek language, Manuscripts, Greek (Papyri), Ostraka 'Sigla and select marginalia in Greek literary papyri' -- subject(s): Antiquities, Greek literature, Manuscripts, Greek (Papyri), Marginalia, Signs and symbols, Textual Criticism
The noun papyrus can be countable or uncountable. In more general, commonly used, contexts, the plural form will also be papyrus. However, in more specific contexts, the plural form can also be papyri e.g. in reference to various types of papyri or a collection of papyri