filtering

1. 1
   noununcountable

   The process of passing a liquid or gas through a filter to remove unwanted material.

   Filtering of the wastewater happens in three stages at the treatment plant.

   The coffee's flavor depends heavily on the filtering during brewing.

   Similarfiltration, straining

2. 2
   verb

   Present participle and gerund of filter.

   The plant is filtering thousands of gallons of water each hour.

   Filtering out spam, the software flags suspicious messages for review.

   Note

   The -ing form carries every use of the verb, and the verb does more than it first appears to. Transitively it sorts or holds back, usually with out: filtering out spam, filtering out noise. Intransitively it means moving gradually, a few at a time, as with light filtering through leaves or guests filtering in. Motorcyclists use it for riding between lanes of traffic. As a gerund it shades into the noun for the process.

   Light was filtering through the shutters by the time we woke.

   Latecomers kept filtering into the hall after the speech began.

3. 3
   noununcountable

   The material that has passed through a filter.

   The filtering from the first pass still contained fine sediment.

   Chemists analyzed the filtering to confirm the impurities were removed.

   Similarfiltrate

   Oppositeresidue

   Note

   What seeps through is often counted in the plural. Abraham Rees's The Cyclopædia (1819) speaks of "the filterings from the subsoils." The word also stretches to light, which can filter as water does: Christopher Rush's To Travel Hopefully (2006) has "the first filterings of daylight." Keep it apart from what the filter holds back. Filterings are what got through, not what was caught.

Showing meanings only. Show all 3