«فَالْإِيجَازُ أَدَاءُ الْمَقْصُودِ بِأَقَلَّ مِنْ عِبَارَةِ الْمُتَعَارَفِ»
Concision conveys the intended meaning with fewer words than the customary formulation.
«وَالْإِطْنَابُ أَدَاؤُهُ بِأَكْثَرَ مِنْهَا»
Expansion conveys it with more words than that formulation.
In this framework, conveying the intended meaning is indispensable. A shorter expression that fails to convey its import is not automatically ījāz; the value of additional words also requires examination.