þúsundum

þúsundum is the dative plural form of the Icelandic word "þúsund," which translates to "thousand" in English. In Icelandic grammar, the dative case is used to indicate various grammatical functions, including the indirect object of a verb, the object of certain prepositions, and to express a variety of adverbial meanings. When referring to thousands of something, the word "þúsund" would take the dative plural form "þúsundum" to agree with the plural noun it modifies or is associated with. For example, if one were to say "with thousands of people," the Icelandic construction would likely involve "með þúsundum manna" (with thousands of men/people). The use of the dative case here signifies a quantity or accompaniment. Understanding this grammatical form is crucial for accurate comprehension and construction of Icelandic sentences when dealing with large numbers or quantities. It is a common inflection encountered in written and spoken Icelandic when discussing plural quantities exceeding one thousand.