"writing room," especially a room set apart in a monastery or abbey for writing or copying manuscripts, 1774, an antiquarian's word, from Late Latin scriptorium "place for writing," noun use of neuter of Latin scriptorius "pertaining to writing," from Latin scriptus, past participle of scribere "to write" (from PIE root *skribh- "to cut"). It was in Middle English in a nativized form, scriptory (early 15c.).
It forms all or part of: ascribe; ascription; circumscribe; conscript; conscription; describe; description; festschrift; inscribe; inscription; manuscript; postscript; prescribe; prescription; proscribe; sans-serif; scribble; scribe; script; scriptorium; scripture; scrivener; serif; shrift; shrive; subscribe; superscribe; superscript; transcribe; scarification; scarify.
It is the hypothetical source of/evidence for its existence is provided by: Greek skariphasthai "to scratch an outline, sketch;" Latin scribere "to write" (to carve marks in wood, stone, clay, etc.); Lettish skripat "scratch, write;" Old Norse hrifa "scratch."