To separate, select, or pick out; to choose and gather or collect.

1. To examine in order to test suitability; SYN. screen out, sieve, sort.
2. To examine methodically; test for suitability.
3. To prevent from entering, as of light; SYN. block out.
4. To project onto a screen for viewing; of films.
5. To test or examine for the presence of disease or infection; SYN. test.

To choose from among a group

1. To join or associate with others, esp. with others of the same kind or species; to agree.
2. To organize or classify, according to kind.