Translation

叔父のような / 親しみ深い年長者らしい / 温かく世話好きな

Meaning

Avuncular describes a person or manner that is warm, kindly, and slightly protective, like a friendly uncle. It often describes an older man, but the key idea is benevolent elderliness, not legal family status.

Examples

• その司会者は温かい叔父のような口調で話した。
  The host spoke in an avuncular tone.
• 教授は新入生に親しみ深い年長者のように助言した。
  The professor gave the new students avuncular advice.