When did the word "Shaykh" begin to be used to denote scholars and students of knowledge, and was it used with this meaning during the era of the Companions and the Tabi'in?

"Shaykh" linguistically refers to one who is old in age and has gray hair; it may also be applied to a person of high status. This word was not a distinctive title for scholars during the time of the Messenger of Allah, peace and blessings be upon him, nor during the time of the Companions or the Successors. Rather, its use became widespread for scholars, hadith narrators, and jurists after the first three centuries.