The building blocks of English

Affixes

-uncle

Forming nouns, chiefly diminutives.

Old French ‑oncle, ‑uncle, or from Latin ‑unculus, a special form of ‑ulus.

This form occurs in a few words, but is not active. Examples are carbuncle (Latin carbunculus, small coal), a severe abscess or multiple boil in the skin; peduncle, the stalk bearing a flower or fruit (Latin pedunculus, from Latin pes, ped‑, foot); furuncle, a technical term for a boil (Latin furunculus, literally ‘petty thief’, also a ‘knob on a vine’, regarded as stealing the sap, from fur, thief).