If you get some gross, unidentifiable substance on the bottom of your shoe, you can call it crud. Basically, crud is anything that's grimy or dirty, especially if you're not sure exactly what it is.
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Noun
an ill-defined bodily ailment; "he said he had the crud and needed a doctor"
Noun
any substance considered disgustingly foul or unpleasant
Noun
heavy wet snow that is unsuitable for skiing
n.
See Curd.
Crud
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Usage Examples
Misspelled Form
Crud, Crud, rud, Crud, Cerud, C4rud, C5rud, Ctrud, Cfrud, Ceud, C4ud, C5ud, Ctud, Cfud, Creud, Cr4ud, Cr5ud, Crtud, Crfud, Cryud, Cr7ud, Cr8ud, Criud, Crjud, Cryd, Cr7d, Cr8d, Crid, Crjd, Cruyd, Cru7d, Cru8d, Cruid, Crujd, Crusd, Crued, Crufd, Cruxd, Crucd, Crus, Crue, Cruf, Crux, Cruc, Cruds, Crude, Crudf, Crudx, Crudc.