一切經音義 18.147

18.147

亘窮（上剛鄧反考聲亘遠也毛詩傳遍也方言竟也或從木作[木*桓]說文從二從日作亘今時所不用𫧍古字也隸書從日從二也）。

Extending to the limit (亘窮: the first character has the fanqie g[āng] + [d]èng; the Kaosheng says: "Gen (亘) means far." The Mao commentary on the Shijing says: "Pervasive." The Fangyan says: "To the end." It is also written with the tree radical as 桓. The Shuowen says it is written with two and sun (日) as 亘, which is no longer used nowadays; 𫧍 is the ancient character; clerical script writes it with sun and two).