Synonyms for Slapdash (same or very similar meaning)
WordNet sense 1 (in a careless or reckless manner):
slam-bang
WordNet sense 2 (marked by great carelessness):
haphazard, slipshod, sloppy
WordNet sense 3 (directly):
bang, bolt, slap, smack
WordNet sense 4 (marked by lack of attention or consideration or forethought or thoroughness; not careful):
careless
From the ODE community, based on WordNet
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