strainer

Short definition from Wiktionary

Noun

1. 1
   A device through which a liquid is passed for purification, filtering or separation from solid matter; anything (including a screen or a cloth) used to strain a liquid.
2. 2
   A perforated screen or openwork (usually at the end of a suction pipe of a pump), used to prevent solid bodies from mixing in a liquid stream or flowline.
3. 3
   Debris in water that blocks the passage of solid objects.
4. 4
   One who strains.