The phrase "well intentioned untruth" refers to a lie told out of good intentions. In other words, it is a falsehood that someone believes will ultimately benefit the person being lied to. Synonyms for this type of lie include "white lie," "tactful deception," or "benign falsehood." It can also be described as "comforting fiction," "kind deception," or "benevolent deception." These phrases all attempt to describe the concept of telling a lie in order to protect someone's feelings or avoid hurting them. Despite the good intentions behind these lies, they can still cause harm and erode trust over time.