Slough

How to spell slough

6 letters · 1 syllable

How to pronounce slough

What does slough mean?

1. verbTo shed or cast off an outer layer, such as dead skin, or to discard something gradually.
2. nounA patch of soft, muddy, waterlogged ground; a swampy hollow.

Slough in a sentence

• verb

  A snake will slough its old skin as it grows.

• noun

  The cart wheels sank into the slough beside the river.

• verb

  The treatment helps the wound slough off dead tissue.

• noun

  After the storm the field became a treacherous slough of mud.

Where does slough come from?

Language of origin: Germanic

This word actually braids together two Old English strands that ended up sharing one tricky spelling. The bog sense descends from Old English slōh, meaning a soft, muddy hollow or mire, which is why a 'slough' is a patch of waterlogged ground where a foot might sink. The verb sense, meaning to shed or cast off, comes from a separate Middle English word, slughe or slou, used for the dead skin a snake leaves behind; it is probably related to Low German and Dutch words for a husk or outer covering. Over the centuries the two converged on the puzzling -ough spelling, which once represented a guttural sound that English later dropped, leaving us with letters that no longer match the way the word is said. That mismatch is exactly the trap: the swamp word is sounded like 'slow' or 'sloo', while the shedding word is sounded like 'sluff', yet both are written identically. The famous Slough of Despond in John Bunyan's Pilgrim's Progress fixed the marsh sense firmly in the literary imagination.

How the word is built

• Single Old English root slōh (a muddy hollow); the -ough spelling preserves a once-pronounced guttural that has since fallen silent