English from Icelandic?
Are there any English words that are of a common or semi-common use that originate from Icelandic?
There are of course many English words borrowed into late Old English and early Middle English from Old West and Old East Scandinavian, the former being the ancestor of modern Icelandic, but English has borrowed very few words from medieval or modern Icelandic. The only one that comes to mind just now is geyser, a late 18th century borrowing of Icelandic Geysir, which is the name of a particular hot spring in southwest Iceland; the name derives from the Old Norse verb geysa ‘to send out with violence’.
There are a few terms that were borrowed into English in Early Modern times or later that could in principle have been borrowed from contemporary Icelandic but in fact were not: rather, they were borrowed from literary Old Norse. Some examples are saga (early 18th century), viking (19th century), and Ragnarok (late 18th century). As these examples suggest, such words are generally associated with early Scandinavian literature and mythology. Other relatively late borrowings that at first sight might appear to be from Icelandic, like troll (Icelandic tröll ‘giant’) and fjord (Icelandic fjörður, in which -ur is an inflexional ending), actually entered English via the Continental Scandinavian languages.
Despite the traditionally conservative Icelandic language policy and the unusually widespread linguistic purism in Iceland, there are actually many more Icelandic borrowings from modern English; this paper by Guðrún Kvaran has a nice (and quite readable) discussion of them.
(Dates are mostly from the Online Etymological Dictionary.)