“ The base is the Teutonic hlaufan, to run, to leap, German laufen. The New English Dictionary considers the Swedish example, löp-knut, “running knot,” and others given by Skeat in support of his derivation to be Germanisms, and also that the pronunciation of the word would have been lowp rather than lūp. “Loop” in meaning (2) “loophole” is also taken to be a different word, and is derived from Dutch luipen, to peer, watch. In modern Dutch the word for a narrow opening is gluip. ”