noun
reverse side of a paper
Literal meaning: the back of a sheet of paper. Not a common everyday word; more often encountered in literary or formal contexts.
紙背にまでインクが染みている。
The ink has soaked through to the reverse side of the paper.
noun
reading between the lines
Abbreviation of 眼光紙背 (がんこうしはい), meaning to perceive the deeper meaning beyond the written words. Used in literary or critical contexts.
See also: 眼光紙背 (がんこうしはい)
彼の批評は紙背に徹している。
His critique penetrates to the meaning between the lines.