ˈfɪltə n. & v. --n. 1 a
porous device for removing impurities or
solid particles
from a
liquid or
gas passed
through it. 2 = filter tip. 3 a
screen or
attachment for
absorbing or modifying
light, X-rays, etc. 4 a device for suppressing
electrical or
sound waves of frequencies
not required. 5
Brit. a an
arrangement for filtering
traffic. b a traffic-light signalling
this. --v.intr. & tr. 1 pass or
cause to pass through a filter. 2 (foll. by through,
into, etc.)
make way gradually. 3 (foll. by out)
leak or cause to leak. 4 Brit.
allow (traffic) or (of traffic) be allowed to pass to
the left or
right at a
junction while traffic
going straight ahead is halted (esp. at traffic lights). øfilter-bed a
tank or
pond containing a
layer of
sand etc. for filtering
large quantities of liquid. filter-paper porous
paper for filtering. filter tip 1 a filter attached to a
cigarette for removing impurities from the inhaled
smoke. 2 a cigarette
with this. filter-tipped having a filter tip. [F filtre f. med.L filtrum felt used as a filter, f. WG]
