WordNet sense 1 (a strainer for separating lumps from powdered material or grading particles):

sieve

WordNet sense 2 (a door that consists of a frame holding metallic or plastic netting; used to allow ventilation and to keep insects from entering a building through the open door):

screen door

WordNet sense 3 (a white or silvered surface where pictures can be projected for viewing):

silver screen, projection screen

WordNet sense 4 (display on the surface of the large end of a cathode-ray tube on which is electronically created):

CRT screen

WordNet sense 5 (a covering that serves to conceal or shelter something):

concealment, cover, covert

WordNet sense 6 (something that keeps things out or hinders sight):

blind

WordNet sense 7 (test or examine for the presence of disease or infection):

test

WordNet sense 8 (examine in order to test suitability):

sort, screen out

WordNet sense 9 (prevent from entering):

block out

WordNet sense 10 (separate with a riddle, as grain from chaff):

riddle

WordNet sense 11 (protect, hide, or conceal from danger or harm):

shield