2 verses have
warn
in Edition Clear Qur'an by Talal Itani / Ghafir (The Forgiver)

40:15Exalted in rank, Owner of the Throne. He conveys the Spirit, by His command, upon whomever He wills of His servants, to warn of the Day of Encounter.

40:18And warn them of the Day of Imminence, when the hearts are at the throats, choking them. The evildoers will have no intimate friend, and no intercessor to be obeyed.