Of these, the smegma bacillus is the only one likely ever to cause confusion.
sebaceous secretion, 1819, from Latin, from Greek smegma "a detergent, soap, unguent," from smekhein "to wipe off, wipe clean, cleanse," from PIE root *sme- "to smear" (cf. Czech smetana "cream," and cf. smear (v.)). So called from resemblance; a medical coinage, the word seems not to have been used in its literal Greek sense in English before this. Related: Smegmatic.
smegma smeg·ma (směg'mə)
A sebaceous secretion, especially the whitish cheesy secretion that collects under the prepuce of the penis or around the clitoris.
Something quite yukky or despicable, as the secretion beneath the male foreskin or around the female clitoris