https://tllpod.podbean.com/e/oscvlvm-panciera/

There were three types of named kisses in Roman culture generally: one for family, one for wives, and one for mistresses. (see basium, savium)

One Emperor outlawed daily kissing (greetings) likely because of a facial disease for which kissing would have increased the spread.

-culum is a Latin diminutive ending, thus os (mouth) + culum (little) = small mouth or kiss

see also: //publikationen.badw.de/de/thesaurus/lemmata#63769