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To catch a crab
What's the meaning of the phrase 'To catch a crab'?
To catch a crab is a term used in the rowing community. It means, either...
1. Catching an oar in the water when moving the oar blade backwards.
2. Missing the water on one's forward pull stroke.
3. Leaving the oar under the water too long on one's forward pull stroke.
The consequence of all three would be, at a minimum, that the rower would get out of sequence with other rowers. More severe crab catching might result in the rower falling backwards in the boat or, in extreme circumstances, falling out of it.
What's the origin of the phrase 'To catch a crab'?
Before we can say much about the origin we need to look closer at the meanings. All three meanings are in use by rowers but clearly they don't correspond and, as the phrase must have originated with one meaning, only one can claim to be the origin.
The expression is a strange one. Why bring crabs into boating blunders? The two analogies that might have been made when the phrase was coined are:
- The oar was caught hold of by a crab when it was in the water.
- The oarsman resembles a crab when falling backwards waving arms and legs in the air.
Both of these crab image notions are plausible. The speculative amongst us might even like to add the idea that, when falling in the water, the oarsmen was diving to catch crabs, but maybe that's a step too far.
There is an earlier Italian phrase 'pigliare un granchio a secco' - literally 'to catch a crab on dry ground' and figuratively 'to make a blunder'. The OED, in the late 19th century when this phrase was coined, and still today, dismisses any thought of there being a connection between the Italian and English phrases. That seems unreliable. The phrase is rather an odd-sounding one and the idea that it was coined independently with much the same 'blunder' meaning in two cultures seems unlikely.
However, even if we accept that the English version derived from the Italian one, all we can glean from that is that the meaning was for the oarsman to have made a mistake. We aren't any nearer to knowing which mistake.
What we can say with some certainty is that the phrase was first recorded in print in Francis Grose's invaluable glossary the 1788 edition of the Classical Dictionary of the Vulgar Tongue:
The action of missing the water with the stroke, or to any other action which causes the rower to fall backward.
Grose was no oarsman and undertook has researches mostly around London.
A discussion in the 1870s in the English scholarly journal Notes and Queries makes it clear that the alternative meanings of 'missing the water with the oar' and 'catching or holding the oar in the water' were both in use at that date. Correspondents from London understood the term to mean the former; those from Cambridge the latter, which explains Grose's definition.
The precise derivation may now be lost to us. What seems most probable is that the Italian term 'to catch a crab' meaning 'make a mistake' was appropriated by British oarsmen. Whenever a rower made a mistake he was said to have 'caught a crab'. What mistake it was varied from place to place.
