Is it ensure, insure, or assure?
Old English webb "woven fabric," from Proto-Germanic *wabjam "fabric, web" (cf. Old Saxon webbi, Old Norse vefr, Dutch webbe, Old High German weppi, German gewebe "web"), from PIE *webh- "to weave" (see weave (v.)).
Meaning "spider's web" is first recorded early 13c. Applied to the membranes between the toes of ducks and other aquatic birds from 1570s. Internet sense is from 1992, shortened from World Wide Web (1990). Web browser, web page both also attested 1990.
webbing web·bing (wěb'ĭng)
A congenital condition in which adjacent structures or parts are joined by a broad band of tissue that is not normally present to such a degree.
A membrane or fold of skin connecting the toes, as of certain mammals.
A structure of delicate, threadlike filaments characteristically spun by spiders.