The Delayer, The Postponer
The One who delays or postpones. The One who puts off advancement.
The One who holds back or keeps something back to put it in its proper place.
The One who causes something to lag behind.
From the root a-kh-r which has the following classical Arabic connotations:
The name Mu'akhkhir is not specifically used as a Beautiful Name in the Qur'ān.
The name al-ākhir (last) also comes from this same a-kh-r root, and is the opposite of awwal (first).
The name Mu'akhkhir (delayer) is the opposite of Muqaddim (promoter).
(Written as al-muakhkhir, the Delayer: ya muakhkhir)