• 佐藤さとう — Sato (common family name)
• 佐官さかん — field officer / mid-ranking officer
• 佐渡さど — Sado Island
• 補佐ほさ — assistant / aide / advisor
• 大佐たいさ — colonel (military rank)
• 少佐しょうさ — major (military rank)

佐 combines the person radical 亻にんべん with 左ひだり. In ancient court ranks, the left side was associated with support or secondary positions. Over time, 佐 came to mean help, assistance, or supportive roles, and today it is also widely seen in family names.

彼かれは 補佐役ほさやくとして 活躍かつやくしています。
He is playing an active role as an assistant.

佐渡さどは 新潟県にいがたけんの島しまです。
Sado is an island in Niigata Prefecture.