This is the 112th most frequent Icelandic word.
árinu
"Árinu" means "the year" in English (definite form, dative case).
"Á þessu árinu" translates to "in this year," emphasizing that the events discussed have occurred within the bounds of the specific year.
Á þessu árinu hefur mikill vöxtur átt sér stað til nýsköpunar.
This year has experienced significant growth in innovation.
"Á árinu" here specifies the person's intention to achieve their goal during the specified or current year.
Ég hef sett mér markmið að klára námið á árinu.
I have set myself the goal to finish my studies within the year.
"Á árinu" indicates "in the course of the year" or "during this year." It is used here to specify a time within the current calendar year.