التضمين
Taḍmīn, incorporating another poet's words.
After iqtibās comes a related but distinct device: a poet inserts a portion of another poet's verse into a new poetic composition so that it functions as part of the later verse. The source is another poet, not the Qur'an or Hadith.
Taḍmīn can enhance expression, but it also raises a question of literary integrity: when should the writer alert the audience that a portion belongs to someone else?