-inqua is a Quenya adjectival ending, seen in alcarinqua "glorious"[1] from alcar "glory". Etymologically, -inqua means "-full", like "glory-full" in this case.
References
- ↑ J.R.R. Tolkien, Christopher Tolkien (ed.), The War of the Jewels, "Part Four. Quendi and Eldar", p. 412