This is the verse translation, not a definition of the individual word.
Say, “Whose testimony is the greatest?” Say, “Allah is Witness between me and you. This Qur’an has been revealed to me so that I may warn you thereby and whomsoever it reaches[1]. Do you really bear witness that there are other gods besides Allah?” Say, “I do not bear such witness.” Say, “Indeed, He is One God, and I disown all that you associate [with Him].”
Source
[1] At every time and place until the Day of Judgment.