The en.wikipedia.org/wiki/ISO_8601β¦ format is YYYY-DDD and the standard and Wikipedia call it an en.wikipedia.org/wiki/Ordinal_β¦.
Regarding the Julian Date term, WP has this to offer:
This system is sometimes referred to as "Julian Date", but this can cause confusion with the astronomical Julian day, a sequential count of the number of days since day 0 beginning 1 January 4713 BC Greenwich noon, Julian proleptic calendar