普門  / pǔ mén /
Universal Gate 
Category:
Terminology 名相
Description:
法法圓通,故名自在;頭頭合道,因號普門。
It is called "at-ease" because all dharmas interpenetrate;
It is named "Universal Gate" because all beginnings lead to the Way,
References:
星雲大師全集【書法類】中華文化佛教名詞 名相 The Complete Works of Venerable Master Hsing Yun: Calligraphy-Terminology 
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