alack has the etymological history: Middle English, probably from the interjection ah + lack ('loss, fault, shame'), expressing dismay; sometimes analyzed as an alteration of alas. Morphologically, the word is transparent as a compound: its parts remain visible in the modern spelling, while the older history of those parts supplies the deeper ancestry. In modern use, the intj sense is "an archaic exclamation expressing sorrow or regret", which keeps the etymology connected to the word's present dictionary value rather than treating it as a merely historical label. The wider word family includes related English forms such as alas, lack, showing how the same base continues to support neighboring English vocabulary. The principal historical forms in the chain include Middle English lac, which anchor the explanation in named linguistic material.