tidelag

From Old Swedish tīdholagh, þȳþilagh, þȳþolagh, compound of thȳdhas (“to have intercourse with”) +‎ lag (“lie down”). The former stems from Old Norse þýða (“to attach oneself to”); compare Swedish ty, Old Norse þýðr. The latter is a verbal noun to ligga (“to lie”), lägga (“to lay”); compare Swedish ligg, English lay (“casual sexual partner”).

tidelag n

1. bestiality (sexual intercourse between humans and animals)

• zoofili

• tidelag in Svenska Akademiens ordböcker
• tidelag in Elof Hellquist, Svensk etymologisk ordbok (1st ed., 1922)