«وأما غير الظاهر فمنه أن يتشابه المعنيان»
“One form of non-apparent borrowing is that the two meanings resemble one another.”
Two poems may differ markedly in vocabulary and surface sense yet resemble each other in an underlying argument, evaluation or relationship. Their affinity is detected by analysis rather than by an obvious verbal repetition.
Before labeling the relationship appropriation, ask whether the shared feature is a commonplace or a genuinely distinctive organization of thought.