Meaning of 'AQIL in English
(Arabic: knowledgeable), in Islamic law, one who is in full possession of his mental faculties. Such a person is legally responsible for his actions and punishable for any deviation from religious commandments. 'Aqil is often used with the adjective baligh (grown-up, or of age) in contrast to qasir (juvenile). In Islamic law, a qasir cannot qualify as a witness in court without consideration of his mental capabilities. For this reason many Muslim scholars directly relate 'aqil to a person's age. Though there is no uniform opinion on the exact age at which an individual becomes an 'aqil, the years 13 to 15 are often mentioned.
Britannica English vocabulary. Английский словарь Британика. 2012