jotun
A member of a race of giants who usually stand in opposition to the Æsir and especially to Thor.
Some with disdain his reasons heard, / While others wisht the cause deferr'd. / Then Ormur spake, in speech of scorn, / Ormur, the friend of Asbiorn, / Who, daring singly to engage, / A jotun, proved his fatal rage.
Where it comes from
Learned borrowing from Old Norse jǫtunn, from Proto-Germanic *etunaz (“giant”). Doublet of ettin.
Adapted from the Wiktionary entry jotun (CC BY-SA 4.0).