familiarissime
familiarissime is a Latin form of familiaris, meaning “of the family; friendly; friend”. It is the superlative adverb.
Found 30 times in the Latin texts on Socratos.
Where it is used
Cicero, Pro A. Cluentio 46: … s et moderata ratio vitae nemo vestrum, ut mea fert opinio, ignorat. his Fabriciis semper est usus Oppianicus familiarissime. iam hoc fere scitis omnes quantam vim habeat ad coniungendas amicitias studiorum ac naturae similitudo. cum …
All forms of familiaris (declension table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Lewis & Short, A Latin Dictionary (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.