An awkward feature or programming technique that ought to be made cleaner. A technique that works acceptably, but which is quite prone to failure if disturbed in the least. For example, a too-clever programmer might write an assembler which mapped instruction mnemonics to numeric opcodes algorithmically, a trick which depends far too intimately on the particular bit patterns of the opcodes.
Many crocks have a tightly woven, almost completely unmodifiable structure.
See kluge , brittle .