bacillary

adjective

ba·​cil·​la·​ry ˈba-sə-ˌler-ē How to pronounce bacillary (audio) bə-ˈsi-lə-rē How to pronounce bacillary (audio)
variants or less commonly bacillar
1
: shaped like a rod
also : consisting of small rods
2
: of, relating to, or caused by bacilli

Word History

Etymology

Medieval Latin & New Latin bacillus

First Known Use

1814, in the meaning defined at sense 1

Time Traveler
The first known use of bacillary was in 1814

Cite this Entry

“Bacillary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bacillary. Accessed 6 Feb. 2026.

Medical Definition

bacillary

adjective
ba·​cil·​la·​ry ˈbas-ə-ˌler-ē How to pronounce bacillary (audio) bə-ˈsil-ə-rē How to pronounce bacillary (audio)
variants also bacillar
1
: shaped like a rod
also : consisting of small rods
2
: of, relating to, or caused by bacilli
bacillary meningitis
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