Sentence:  "<WSD>Denial</WSD>" came out of the therapyspeak prevalent in the middle of the 20th century, especially as it was applied to confronting the reality of mortality. It was popularized as the first stage of grief, and quickly expanded to include refusal to confront any bad news or disturbing ideas. 
Meaning of the word marked with <WSD> tags:  A defense mechanism involving a refusal to accept the truth of a phenomenon or prospect.