An uncle (father's or mother's brother). 伯父さん (older than one's parent) and 叔父さん (younger than one's parent) distinguish age relation.
伯父さんが来週、家に遊びに来る予定だ。
My uncle (older than my parent) is coming to visit next week.
子どもたちは叔父さんと公園へ行った。
The children went to the park with their uncle (younger than their parent).
An older man; used familiarly or vocatively to address or refer to middle-aged men (often translated as 'mister' or 'old man').
あそこのおじさんに道を聞いてみよう。
Let's ask that man over there for directions.
市場で小父さんが魚を売っていた。
An older man was selling fish at the market.
A fish name (manybar goatfish, Parupeneus multifasciatus) — used as a common name in some regions (often written オジサン).
この海域ではオジサンがよく釣れる。
In this sea area, manybar goatfish (ojisan) are often caught.