From The Collaborative International Dictionary of English v.0.48:
Screen \Screen\ (skr[=e]n), v. t. [imp. & p. p. Screened; p.
pr. & vb. n. Screening.]
1. To provide with a shelter or means of concealment; to
separate or cut off from inconvenience, injury, or danger;
to shelter; to protect; to protect by hiding; to conceal;
as, fruits screened from cold winds by a forest or hill.
[1913 Webster]
They were encouraged and screened by some who were
in high commands. --Macaulay.
[1913 Webster]
2. To pass, as coal, gravel, ashes, etc., through a screen in
order to separate the coarse from the fine, or the
worthless from the valuable; to sift.
[1913 Webster]
3. to examine a group of objects methodically, to separate
them into groups or to select one or more for some
purpose. As:
(a) To inspect the qualifications of candidates for a job,
to select one or more to be hired.
(b) (Biochem., Med.) to test a large number of samples, in
order to find those having specific desirable
properties; as, to screen plant extracts for
anticancer agents.
[PJC]