This article examines the role of words in cognitive operations and their impact on deep understanding and the transfer of concepts in Nahjul-Balaghah. Focusing on the word “oḥall” in Letter 18 of Nahjul-Balaghah, its lexical meaning, synonyms, and various uses are analyzed to demonstrate the importance of careful selection of words in creating cognitive and lasting effects. The results show that “oḥall” in lexical sources refers to the meanings of opening, lifting a ban, opening, allowing, and relaxing, and synonyms such as “أَبَاحَ”, “أَنْزَلَ”, “أَسْقَنَ”, “آوَى”, “یِسْتَضَافَ”, “رَخَّصَ”, “سَوَّغ”, “سَمْح”, “أَتقلَ”, and “فک” have been examined in Nahjul-Balaghah. The correspondence of the uses of these words in Nahjul-Balagha with their lexical and cultural meanings indicates the precision and elegance of Imam Ali (peace be upon him) in using words, which play an important role in the impact and effectiveness of moral and educational messages; and it shows the Imam's precision in choosing the four words "saugha", "samha", "atlaq" and "faq" in Nahjul-Balagha as synonyms for the word "ohalal". Also, analyzing the semantic aspects of the word "ohalal" and examining historical and rhetorical examples shows that this word Finally, emphasizing the importance of careful selection of words in conveying deep meanings