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

sicker \sick"er\, v. i. as. sicerian. mining
   to percolate, trickle, or ooze, as water through a crack.
   also written sigger, zigger, and zifhyr. prov. eng.
   1913 webster sicker
see also:
sigger zigger zifhyr 

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

zigger \zig"ger\, zighyr \zig"hyr\, v. i. mining
   same as sicker. prov. eng. --raymond.
   1913 webster
see also:
sicker 

Zigger >> Z Words
Zigger, definition of term: Zigger
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