Complex sentence: The English word is attested from the early 18th century but remains obscure until the early 19th century, when it is taken up by authors of Romanticist collections of fairy tales and becomes mostly synonymous with the older word "goblin".
Split into simpler sentences: The English word is attested from the early 18th century. Other uses of the term gnome remain obscure until the early 19th century, when it is taken up by authors of Romanticist collections of fairy tales and becomes mostly synonymous with the older word "goblin".