[1] : The Collaborative International Dictionary of English v.0.48

gabel \ga"bel\, n. f. gabelle, ll. gabella, gabulum, gablum; of
   uncertain origin. cf.gavel tribute. o. eng. law
   a rent, service, tribute, custom, tax, impost, or duty; an
   excise. --burrill.
   1913 webster

         he enables st. peter to pay his gabel by the ministry
         of a fish.                               --jer. taylor.
   1913 webster
see also:
gavel 

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

gabel. a tax, imposition, or duty. this word is said to have the same 
signification that gabelle formerly had in france. cunn. dict. h. t. but 
this seems to be an error for gabelle signified in that country, previously 
to its revolution, a duty upon salt. merl. rep. h. t. lord coke says, that 
gabel or gavel, gablum, gabellum, gabelletum, galbelletum, and gavillettum 
signify a rent, duty, or service, yielded or done to the king or any other 
lord. co. litt. 142, a. 

Gabel >> G Words
Gabel, definition of term: Gabel
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