Etymology: Apparently originally < early Scandinavian (compare Old Icelandic rif , Norwegian rev , (Nynorsk) riv , Swedish rev (1698), Danish reb , †rev ); these forms are probably (originally denoting a strip of fabric) < the Scandinavian base of Old Icelandic rífa to tear off (see rive v.¹); compare (with different ablaut grade) Old English arāfian to roll up. In later use (chiefly in β. forms) apparently reborrowed < Dutch reef, rif (16th cent.; compare Middle Dutch rēve in an apparently isolated attestation with reference to the sails of windmills) and the related Middle Low German ref (German regional (Low German) Reef, Reff; > German Reff, †Reef), both ultimately either cognate with or < the early Scandinavian word. Compare Anglo-Norman and Old French (Normandy) ris (1155; French ris), apparently arising from a plural *rifs of a borrowing < the early Scandinavian word.Dutch reef is a secondary singular form arising from the plural form rēven , which is historically the plural form corresponding to singular rif (showing open syllable lengthening in the plural form). Forms with a long vowel in other languages are probably < Dutch (compare β. forms). With the γ. forms compare early modern Dutch rift (1599 in Kiliaan, cited as a variant of rif ), also early modern Danish rift . Compare rift n.¹ Old Icelandic rif is formally identical with rif rib n.¹, and has also been interpreted as a transferred use of that word; compare reef n.² With to take in a reef at sense 1a compare Dutch een rif inbinden (1599 in Kiliaan). Compare also later reef v.¹

Etymology: < early modern Dutch riffe, riff (Dutch rif ) and the related Middle Low German rif, ref (German regional (Low German) Reff , Riff ; > German Riff ), both apparently < early Scandinavian (compare Old Icelandic rif , Faroese riv , Norwegian rev , (Nynorsk) riv , Swedish rev (1577 as räff ), early modern Danish reff , riff (Danish rev )), probably a transferred use of the early Scandinavian cognate of rib n.¹ (compare Scandinavian forms cited at that entry). With sense 2 compare earlier rib n.¹ 13.With the semantic development of the early Scandinavian word compare Dutch rib sandbank, reef (1630), specific use of rib rib n.¹ The β. forms apparently arose from lengthening of the vowel of the α. forms; it is perhaps possible that association with the formal variation shown by reef n.¹ may have played a part in their spread. Compare Orkney and Shetland Scots rif, riv ridge or bank of rock jutting out into the sea (frequently in place names) < the unattested Norn reflex of the early Scandinavian word represented by the Scandinavian forms listed above.

Etymology: Origin uncertain. Perhaps a variant of riff n.² (compare discussion of forms at reef n.²), or perhaps < reof adj. Compare earlier rove n.²The following quot. may perhaps show a much earlier example of the word (in Old English); however, it is more likely that the form is simply a scribal error (H. J. de Vriend in his edition of the text cited emends hreofe to hreofle, dative singular of hrēofl scabbiness, itching, rash):OE tr. Medicina de Quadrupedibus (Vitell.) vii. 256 Wið hreofe [OE Hatton hreofe; prob. read hreofle] & wið toflogen lic, genim þæt wæter þe innan gæt byþ.

Etymology: < reef n.¹ Compare Dutch reven (1673), German reffen , †reefen (18th cent.), Swedish reva (1672 as refva ), Danish reve , rebe (in early modern Danish as repe ). Compare earlier to take in a reef at reef n.¹ 1a. In forms reeve, reve perhaps partly influenced by reeve v.¹

Etymology: < reef n.² Compare slightly earlier reefing n.² and reefer n.²