圆筒

• 囗(encircling ring; surrounding loop)RADICAL
• 员(member)PHONETIC

A circle is a shape that is completely enclosed and closed like a member held within embracing arms.

• ⺮(bamboo)RADICAL
• 同(together; same)PHONO-SEMANTIC

A hollow bamboo tube is empty inside, just like everything flows through together in unity of purpose.