Where does “siamesisk tvilling” come from?

siamesisk tvilling (Swedish) comes from Swedish tvilling, from Old Swedish tvinlinger, from Old Norse tvinlingr, from Proto-Germanic twinilingaz, from Proto-Germanic -ilingaz, from Proto-Germanic -ilaz, from Proto-Indo-European -lós — Forms agent nouns from verbal roots.

siamesisk tvilling (Swedish): a Siamese twin, a conjoined twin

Definitions

  1. a Siamese twin, a conjoined twin

Ancestry of “siamesisk tvilling”, step by step

siamesisk tvilling traces back through two separate lines of ancestry.

via Swedish tvilling

StepLanguageWordMeaning
1Swedishtvillingtwin
2Old Swedishtvinlinger
3Old Norsetvinlingr
4Proto-Germanictwinilingaz
5Proto-Germanic-ilingazForms noun-derivatives with sense of 'belonging...
6Proto-Germanic-ilazagent suffix; diminutive suffix
7Proto-Indo-European-lósForms agent nouns from verbal roots

via Danish siamesisk

StepLanguageWordMeaning
1DanishsiamesiskSiamese
2Danish-esisk-ese, -ish; forms adjectives from proper nouns
Every word from Proto-Indo-European -lósEvery word from Proto-Germanic -ilazEvery word from Proto-Germanic -ilingaz