There appears to be something in the etymology to support this.
Nīvaraṇa (nt. occasionally m.) [Sk. *nivāraṇa, nis+ varaṇa of vṛ (vṛṇoti),
see nibbuta & cp. nivāraṇa]
Nibbuta (adj.) [Nibbuta represents Sk. nirvṛta (e. g. AvŚ i.48) as well as nivṛta, both pp. of
vṛ, which in itself combines two meanings, as exhibited in cognate languages and in Sk. itself: (a) Idg. ṷer
to cover, cover up (Lat. aperio=*apa -- veri̯o to cover up, Sk. varutram upper garment, "cover") and (b) *ṷel to resolve, roll, move (Lat. volvo=revolve; Gr. e(/lic, e)lu/w; Sk. vāṇa reed=Lat. ulva; Sk. ūrmi wave; P. valli creeper, valita wrinkled). *ṷer is represented in P. by e. g. vivarati to open, nivāreti to cover, obstruct, nīvaraṇa, nivāraṇa obstruction;
http://dsal.uchicago.edu/cgi-bin/philol ... 1:350.paliSo it looks like there could be a sense of nivarana as something that "covers" or obscures something else.
"When one thing is practiced & pursued, ignorance is abandoned, clear knowing arises, the conceit 'I am' is abandoned, latent tendencies are uprooted, fetters are abandoned. Which one thing? Mindfulness immersed in the body." -AN 1.230