svangur.

From Old Norse svangr (“slender, slim, thin”), from Proto-Germanic *swangaz (“thin, slim”). The original meaning in Germanic was probably 'curved inwards', discernible from the derived Old Norse svangi (“flank, groin”), i.e., 'the sides of the abdomen which curve inwards slightly'. Within Icelandic the meaning developed from 'thin' to 'feeling hungry'. Cognates are Faroese svangur (“hungry”), Danish svang (“thin, famished”), Norwegian svang (“hungry”), dialectal Swedish svånger (“thin, hungry, empty”), Middle Swedish svanger (“slender, emaciated, very thin”), Middle High German swanger (“flexible, slender”). Further origin unsure, perhaps related to Middle Irish seng (“narrow, thin”). Not related to Danish svanger, Norwegian svanger, Dutch zwanger, German schwanger (“pregnant”).

A noun of the adjectival form svangur (“hungry; thin”). Compare the Old Norse svangi (“the groins, especially of animals”) which was also spelled svangr (“the groins, especially of animals”).