Is Suhrawardi's criticisms of the peripatetic concept of definition, and the establishment of the Ishraqi theory of definition by him, a sharp divergence of Ibn Sina’slogic of the definition? Some scholars think that the answer is yes, however thepresent paper’s answer to this question is ‘no’. In Hekmat al-Ishehraq,Suhrawardihas three basic criticisms to the theory of completeessential definition, some of which can be generalized to the incomplete essential definition and also accidental definitions: (1) conflicts with the conventional use of language; (2) the incomprehensibility of the realdifferences; (3) the perpetual probability of neglect of one or more intrinsic features. The bold veins of these three critiques can be found in the treatise of Ibn Sina’sal-Hodoodva al-Ta'lighat, along with two other criticisms: (4) theperpetual probability of theacquisition ofrequisite rather than essence; and (5) the perpetual probability of the acquisition of remote genus instead of close genus. The only possible definition fromSuhrawardi point of view is the definition of quiddity through the combination of general accidents that are belonged to thatquiddity, provided that the definition proceeds in the epistemological trades between definiens and definiendum and on the basis ofdirect(unmediated) knowledge.This theory is also the extender of the line Ibn Sina has drawn in Al-Ta'lighatva Al-Isharat. Therefore, Suhrawardi'slogic of definition complementsthe Avicenna's logicofdefinition.