Some seven letter nouns that start with D and with N are:
tarsi
evolve
Source
canal
Prestidigitate.
pour
sienna bro
critic
queer Meaning odd, not in a homophobic way queer Queer
A circle has no starting or ending point of a circle. Hope this helps!
Likely candidate is the word: Inform.
The starting year was 1802 and the ending year was 1822.