The Collaborative International Dictionary of English v.0.48:

Crud \Crud\ (kr?d), n.
   See Curd. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Curd \Curd\ (k[^u]rd), n. [Of Celtic origin; cf. Gael. gruth,
   Ir, gruth, cruth, curd, cruthaim I milk.] [Sometimes written
   crud.]
   1. The coagulated or thickened part of milk, as distinguished
      from the whey, or watery part. It is eaten as food,
      especially when made into cheese.
      [1913 Webster]

            Curds and cream, the flower of country fare.
                                                  --Dryden.
      [1913 Webster]

   2. The coagulated part of any liquid.
      [1913 Webster]

   3. The edible flower head of certain brassicaceous plants, as
      the broccoli and cauliflower.
      [1913 Webster]

            Broccoli should be cut while the curd, as the
            flowering mass is termed, is entire.  --R. Thompson.
      [1913 Webster]

            Cauliflowers should be cut for use while the head,
            or curd, is still close and compact.  --F. Burr.
      [1913 Webster]

WordNet (r) 3.0 (2006):

crud
    n 1: heavy wet snow that is unsuitable for skiing
    2: any substance considered disgustingly foul or unpleasant
       [syn: filth, crud, skank]
    3: an ill-defined bodily ailment; "he said he had the crud and
       needed a doctor"

The Free On-line Dictionary of Computing (30 December 2018):

CRUD

    A mnemonic for the four most important
   kinds of activity that almost any system of any type needs to
   support: create, read, update, delete.  The absence or failure of
   any one of these is often a sign of a bad design or poor testing.

   (2014-08-06)