bacillary a relating to or produced by or containing bacilli s formed like a bacillus Usage(s) The bacteriophage of bacillary dysentery has been employed by the Oswaldo-Cruz Institute in Brazil to eradicate bacillary dysentery in that country. A high bacillary count, in turn, is almost always found to be associated with a high rate of decay. Another outbreak of bacillary dysentery was reported last week from Northampton, Mass. Synonym(s) bacillar bacilliform baculiform rod-shaped