Nest is the medieval Welsh form of Agnes — meaning "pure." Princess Nest ferch Rhys (c. 1085-1136), called the "Helen of Wales," was the famously beautiful daughter of the last king of Deheubarth — through her descendants run the FitzGerald dynasty and many Welsh-Norman royal lines.
Nest is rare but iconic in Welsh history.
Nest reduces to one — the number of Welsh Helen.