anxiousness comes from anxious + -ness, from Latin anxius ('troubled, distressed'), from angere ('to choke, cause distress'), from Proto-Indo-European *h₂enǵʰ- ('tight, painfully constricted'). Morphologically, the word is transparent: -ness is attached to the older base named in the history, so the modern form packages an inherited or borrowed stem inside a later English derivative. In modern use, the noun sense is "the state of being uneasy or worried; nervous apprehension", 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 anxious, anxiety, anguish, showing how the same base continues to support neighboring English vocabulary. The principal historical forms in the chain include Latin anxius, Proto-Indo-European *h₂enǵʰ-, which anchor the explanation in named linguistic material.