The Collaborative International Dictionary of English v.0.48:

Serigraph \Ser`i*graph\, n. [L. sericum silk + E. -graph.]
   An autographic device to test the strength of raw silk.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

serigraph
    n 1: a print made using a stencil process in which an image or
         design is superimposed on a very fine mesh screen and
         printing ink is squeegeed onto the printing surface through
         the area of the screen that is not covered by the stencil
         [syn: silkscreen, silk screen print, serigraph]