Ångström

1) Örmýrjungur
(The Íslensk orðsifjabók mentions for the obsolete mýr: 'mergð, grúi'. vafaorð, e.t.v. s.o. og myr (s.þ.) en ý tilkomið vegna þess að lærðir menn tengdu það við lat. Mýrias, gr. Mýrias (ef. Mýriados) 'tíu þúsund' af 'mýrios' (ótölulegur). The ideal construction of a name for "one ten thousandth part is, in my opinion, is “mýr-” or “mýríu-” (10,000) combined with -jungur (100) as in the construction þriðjungur (a third).
The addition of the prefix ör- (yes, I know mikró- is used in Icelandic translation of metrical prefixes, but that's only a convention. One could as well use ör in this sense), örmýrjungur, which means the 'ten billionth part'. We can use this for ångström. There's no need to add -stika or -metri. Most scientists will link up the notion "ten billionth part" with an ångström.)

2) Angstreymingur
(The Swedish toponymical surname Angström icelandicizes as 'Angstraumur'. The Icelandic collective family name would be 'Angstreymingar', the singualr form of which denotes an individual belonging to that family or group of follower. Angstreymingur is the logical name of the unit.)

3) rófstika (róf- spectro- + stika (unit)).
The ångström is still the predominantly used unit in spectroscopy.