catch a crab
v. phr.— «And they oohed with disappointment when another boat stopped dead in the water as one of the rowers “caught a crab” as they say in the sport: An oar caught water and was pulled downward resulting in an urgent need to halt the boat.» —“They pull for East Hartford High” by John Karas East Hartford Gazette (Connecticut) Oct. 30, 2008. (source: Double-Tongued Dictionary)
Further reading
A retronym is a word coined to distinguish something new from an older, more generic version, such as electric guitar or clock radio. A couple of new retronyms are fine water, or “unprocessed water that reflects a region’s terroir” and water...
For at least three centuries, declaring I’ll eat my hat! has indicated that the speaker is so certain they’re right, that if they’re not, they’re willing to swallow their chapeau. Variations of this phrase include I’ll eat my boots, I’ll eat my cap...
This phrase appears in “Through the Looking Glass”, Chapter 5 (in which Alice suddenly finds herself rowing in a boat with the Sheep):
“‘Feather! Feather!’ the Sheep cried again, taking more needles. ‘You’ll be catching a crab directly.'”
alot of older inmates use it on the newer inmates “catch a crab”,
seeking out fresh meat or punk them out.