Definition of "sluff"

The Scouts learned from expert Keith Burke that snow avalanches come in different forms. A powder or "sluff" avalanche starts at a single point and fans out as surface snow slides downhill. These avalanches are not as violent as slab avalanches. Slab avalanches are very dangerous. They occur when a whole hillside of snow breaks loose in a giant slab, which then breaks into snow blocks that tumble downhill faster and faster.

2001 Mar, Buck Tilton, “Cold Comfort”, in Boys Life, volume 91, number 3, page 18

At least for small sluffs like the ones Brown and his colleagues have triggered, the avalanche slides like a block of material instead of flowing like a fluid.

2002 March 2, Sid Perkins, “Avalanche! Scientists are digging out the secrets of lethal flows of snow.”, in The Free Library‎

While I found wonderfully soft and untracked snow near the top, I ended up surprised by the firmer stuff in the chutes near the bottom, where small slides had sluffed away the soft, top layer.

1995 Jan, Peter Oliver, “Easy Doesn't Do It”, in Skiing, volume 47, number 5, page 24

After temperatures warm up a little, however, the snow will "sluff", or slide, down the front of the windshield, often in small slabs.

2011 October 10, “Anatomy of an avalanche”, in Encyclopedia of Earth‎

Blaser, for whom the rumored death of his program has been an annual affair, recalled the other day how nervous he was the first time he heard swimming might be cut his freshman year and how it became easier to sluff off the rumors.

1996 January 29, Kevin Acee, “Several coaches are worried over what will happen to their sports”, in The Free Library‎, archived from the original on 26 April 2013

If either played another club, declarer would ruff on the board and sluff his diamond queen.

2009 February 16, Phillip Alder, “At a Florida Game, an Unusual Double Squeeze”, in New York Times‎

Both calls told her the same thing — that her son had been sluffing school. She felt betrayed. She had trusted this child.

Sunshine for the Latter-Day Saint Mother's Soul