المعنى الاصطلاحي :

Seeking the establishment and affirmation of a right through a certain means with the purpose of preserving it.

الشرح المختصر :

"Isteethāq" (authentication) of transactions through one of the means of "isteethāq" is permissible, for people need it in their dealings to avoid the potential denial or loss of their rights and to retrieve information easily in cases of dispute or forgetfulness. Means of "isteethāq" include: writing down, issuing muniments, pawning, having witnesses, undertaking, suretyship, right of retention, etc. "Isteethāq" expires with the termination of its cause. For example, retention of the pawned item ends by the repayment of the debt, whereupon the pawned item should be released and delivered to the pawner.

التعريف اللغوي المختصر :

"Isteethāq": strengthening, consolidating. It is derived from "wathāqah" and "tawtheeq", which mean precision and exactness. Other meanings: requesting a "watheeqah" (documentation), granting or seeking security, tightening, tying, fastening, fettering, preservation.