In articulo mortis is Latin for at the point of death
in articulo mortis In the grasp of death or at the moment of death. A statement made in articulo mortis, 'at the point of death', carries special weight; since it is believed that a person about to die has nothing to gain, perhaps much to lose, by lying.
(a statement made) at the point of death - traditionally statements made 'in articulo mortis' have at times been considered additionally believable because the person had nothing to gain at that stage from lying - alternative to 'in extremis'