What does : mean in Latin?

:, a punct, means “Used to mark abbreviations.; A word divider.”.

:

Medieval LatinNew LatinUsed to mark abbreviations.
This verse translation was entered in the manuscript in a secretary hand that Rugh Hughey, the editor of the Arundel Harington manuscript, tentatively assigned to the mid- or late sixteenth century; in the right margin at the end of the text, an italic hand of uncertain date has written “E.R. Ꝑ re:”.[…]these letters can be expanded to “per re-----.”c. 16th century, manuscript, quoted in “Elizabeth I: Translations, 1544–1589” (in English), Janel Mueller, Joshua Scodel, editors, 2009, →ISBN, page 460:
BRİDGET. HOLMES / ETA:^S SUÆ: 96 / A:D:1686:· BRIDGET. HOLMES / ETA[TI]S SUAE 96 / A[NNO] D[OMINI] 1686:·1686, John Riley, portrait of Bridget Holmes (image), inscription at the bottom left corner
LatinarchaicA word divider.
𐌌𐌀𐌍𐌉𐌏𐌔:𐌌𐌄𐌃:𐌅𐌇𐌄⁝𐌅𐌇𐌀𐌊𐌄𐌃:𐌍𐌖𐌌𐌀𐌔𐌉𐌏𐌉Manius made me for Numerius.7th century BCE, Praeneste fibula:
𐌂𐌀𐌔𐌕𐌏𐌓𐌄𐌉:𐌐𐌏𐌃𐌋𐌏𐌖𐌒𐌖𐌄𐌉𐌒𐌖𐌄 / 𐌒𐌖𐌓𐌏𐌉𐌔To Castor and Pollux/Polydeuces, the Dioscuri.6th–5th century BCE, dedication to Castor and Pollux, Lavinium, Latium, →JSTOR: