grăphis — Lewis & Short
grăphis, ĭdis and ĭdos, f., = grafi/s.
I A drawing-pencil, sketching-pen: pingere collibitum est: graphidem date, Ser. ap. Diom. p. 516 P.—
II Transf., drawing; a draught, design:
architectum oportet graphidos scientiam habere,Vitr. 1, 1, 4:
alias multa graphidis vestigia exstant in tabulis ac membranis ejus,Plin. 35, 10, 36, § 68.