adag-

verb. to build, erect, establish

This verb appeared as ᴱN. adag- “build” in the Early Noldorin Grammar of the 1920s, with an infinitive form of adog/adob (PE13/132). The same verb forms appeared in Early Noldorin Word-lists from this same period, with a gloss of “to build” or “to build, erect” derived from ᴱ✶a-tak, and with ᴱN. adob also being a noun for “a building” (PE13/136, 158). In contemporaneous notes on Early Qenya Phonology, Tolkien gave the verb form as adab- “build, establish” derived from ᴱ✶ataku̯- under the early root ᴱ√tak- “stick, [stick] in, fix, firm” (PE14/66).

Conceptual Development: The Gnomish Lexicon of the 1910s had G. bada- “to build”, related to G. bad “building, outhouse, shed” (GL/21).

Neo-Sindarin: Since N. adab “building, house” appeared under the root ᴹ√TAK in The Etymologies (Ety/TAK), I would retain this verb as ᴺS. adaba- “to build, erect, establish” for purposes of Neo-Sindarin, a blending of the various early verb forms. The final a helps keep its past forms distinct from S. tag- “fix”.