Below are possible answers for the crossword clue Filter problem.
6 letter answer(s) to filter problem
RIDDLE
a coarse sieve (as for gravel)
a difficult problem
explain a riddle
pierce with many holes; "The bullets riddled his body"
separate with a riddle, as grain from chaff
set a difficult problem or riddle; "riddle me a riddle"
speak in riddles
spread or diffuse through; "An atmosphere of distrust has permeated this administration"; "music penetrated the entire building"; "His campaign was riddled with accusations and personal attacks"
Other crossword clues with similar answers to 'Filter problem'