familiarities
fəmɪlɪˈarɪti
noun
relaxed friendliness or intimacy between people.
familiarity allows us to give each other nicknames
informality,casualness,ease,comfortableness,friendliness,lack of ceremony,lack of restraint,lack of reserve,naturalness,simplicity,closeness,intimacy,attachment,affinity,friendship,amity,chumminess,palliness,mateyness