1. to pierce with numerous holes; perforate: riddle a target with bullets.
2. to spread throughout: "election campaigns have always been riddled with demagogy and worse” ( new republic).
3. to put (gravel, for example) through a coarse sieve.
4. A coarse sieve, as for gravel.
5. A question or statement requiring thought to answer or understand; a conundrum.
6. one that is perplexing; an enigma.
7. to solve or explain.
8. to propound or solve riddles.
9. to speak in riddles.

1. A verbal puzzle, mystery, or other problem of an intellectual nature, such as "it's black, and white, and red all over. what is it?"
2. to speak ambiguously or enigmatically.
3. to solve, answer, or explicate a riddle or question
4. A sieve.
5. to fill with holes.
6. to fill or spread throughout; to pervade.
7. to put something through a sieve

1. A sieve with coarse meshes, usually of wire, for separating coarser materials from finer, as chaff from grain, cinders from ashes, or gravel from sand.
2. A board having a row of pins, set zigzag, between which wire is drawn to straighten it.
3. something proposed to be solved by guessing or conjecture; a puzzling question; an ambiguous proposition; an enigma; hence, anything ambiguous or puzzling.
4. to speak ambiguously or enigmatically.
5. to separate, as grain from the chaff, with a riddle; to pass through a riddle.
6. to perforate so as to make like a riddle; to make many holes in.
7. to explain; to solve; to unriddle.

1. to explain; interpret; solve; unriddle.
2. to understand; make out.
3. to puzzle; perplex.
4. to speak in riddles, ambiguously, or enigmatically.
5. to sift through a riddle or sieve: as, to riddle sand.
6. to sift by means of a coarse-netted dredge, as young oysters on a bed.
7. to reduce in quantity as if by sifting; condense.
8. to fill with holes; especially, to perforate with shot so as to make like a riddle; hence, to puncture or pierce all over as if with shot; penetrate.
9. to use a riddle or sieve; pass anything through a riddle.
10. to fall in drops or fine streams, as through a riddle or sieve.
11. to plait.
12. A proposition so framed as to exercise one's ingenuity in discovering its meaning; an ambiguous, complex, or puzzling question offered for solution; an enigma; a dark saying.
13. anything abstruse, intricate, paradoxical, or puzzling; a puzzle.
14. A person who manifests ambiguities or contradictions of character or conduct.
15. A sieve, especially a coarse one for sand, grain, and the like.
16. in founding, a sieve with half-inch mesh, used in the molding-shop for cleaning and mixing old floor-sand.
17. in hydraulic engineering, a form of river-weir.
18. in wire-working, a flat board set with iron pins sloped in opposite directions. it is used to straighten wire, which is drawn in a zigzag course between the pins.
19. A curtain; a bed-curtain; in a church, one of the pair of curtains inclosing an altar on the north and south, often hung from rods driven into the wall.
20. in minting. see the extract.

1. speak in riddles
2. set a difficult problem or riddle
3. pierce with many holes
4. a difficult problem
5. spread or diffuse through
6. explain a riddle
7. separate with a riddle, as grain from chaff
8. a coarse sieve (as for gravel)