From Longman Dictionary of Contemporary Englishavunculara‧vun‧cu‧lar /əˈvʌŋkjələ $ -ər/ adjective FRIENDLYbehaving in a kind and nice way to someone who is younger, rather like an uncle an avuncular pat on the shoulder
Examples from the Corpus
avuncular• He had to admit that it was not unpleasant to be taken in hand by some one so positive and avuncular.• We really only knew him through childhood over-the-counter dealings smiling, ever-patient, avuncular.• Under other circumstances she might have found it avuncular but now it was oppressive.• He is capable of avuncular charm, wheezy laughter and mischievous wit as well as grizzly ferocity and stick-in-the-mud reactionary attitudes and walking-stick-in-the-hand swashbuckling.• Harry Lucas was to all of us who knew him a mentor, a tutor and avuncular friend.• Sam gave her an avuncular squeeze.• Just keep an avuncular, supervisory eye on them.Origin avuncular (1800-1900) Latin avunculus; → UNCLE