n 1 cap : a genus of slender white nematode worms of the family Trichuridae that includes serious pathogens of the alimentary tract of fowls and some tissue and organ parasites of mammals including one (C. hepatica) which is common in rodents and occas. invades the human liver sometimes with fatal results 2 : a nematode worm of the genus Capillaria cap*il*lar*id n
Similar sounding terms: capillary
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