Any of various electric, electronic, acoustic, or optical devices used to reject signals, vibrations, or radiations of certain frequencies while allowing others to pass.
A colored glass or other transparent material used to select the wavelengths of light allowed to reach a photosensitive material.
Computer Science A program or routine that blocks access to data that meet a particular criterion: a Web filter that screens out vulgar sites.
To pass (a liquid or gas) through a filter.
To remove by passing through a filter: filter out impurities.
Computer Science To use a filter to block access to (a website or Web content).
To pass through or as if through a filter: Light filtered through the blinds.
To come or go gradually and in small groups: The audience filtered back into the hall.