What does "slapdash" mean?

Slapdash: With a slap; all at once; slap. [Colloq.] Prior.

Additional senses

  1. 2.To apply, or apply something to, in a hasty, careless, or rough manner; to roughcast; as, to slapdash mortar or paint on a wall, or to slapdash a wall. [Colloq.] Halliwell.

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