bak- / Indo-European roots
Examples of words with the root bak-: bacillus, bacterium, baculiform, baculum, baguette, debacle, imbecile.
Staff used for support.
a. bacillus, baculum, baguette, bail4, bailey; baculiform, debacle, imbecile from Latin baculum, rod, walking stick;
b. Possibly Latin imbēcillus, imbecillus, feeble, possibly from *in-bacillus , "without a staff (to steady oneself), without support" from bacillus, diminutive of baculum (in-, not; see ne) imbecile.
2. bacterium; corynebacterium from Greek baktron, staff.
[Pokorny bak- 93.]