Aravir (T.A. 2156 - 2319, died aged 163) was the fourth Chieftain of the Dúnedain, following his father, Aranuir, upon his death in 2247.
As far as we know, Aravir's rule was uneventful, except for the usual skirmishes with orcs. However, during his rule the Watchful Peace slowly came to an end as Sauron returned to the north-west of Middle-earth, although his presence remained unknown.
Aravir died in 2319, after having been Chieftain for seventy-two years) and was followed by his son Aragorn I (after whom Aragorn Elessar was named).
Arahael's name is Sindarin, and although the etymology is uncertain, it probably means "Royal Jewel", coming from the prefix ara- meaning "king", and mir (becoming lenited to vir) meaning "jewel".