@stevesmi
I think almost all, if not all nouns, may be used as root words, but not all root words are nouns. Some of them may be verbs.
In TLDCAdmin's example, I would consider "punta" more as a verb that means "go to a destination". "Kada-punta" would be an adverbial phrase that means "each time someone goes somewhere".
In "Punta ka dito", "punta" is the shortened form for "pumunta" or "magpunta".
"Pumunta/Magpunta/Punta ka dito". = You, come here.
The noun form of "punta" would be "punt
ahan" (a favorite destination).
"Ang Niagara Falls ay kilal
áng punt
ahan ng mga tur
ista. " = The Niagara Falls is a well-known favorite destination of tourists.
Where the stress falls in a word may also change its meaning. "Punt
ahan" is a noun, but "puntah
án" is a verb.
"Puntah
án natin ang Niagara Falls." = Let's go to the Niagara Falls.
"K
ain" = eat
"Kum
ain" = to eat
"Pagk
ain" = food
"Ka
inin" = to eat something
"Ka
inan" = to eat a portion of something
"Kain
án" = a place to eat (may mean a plate, a table, a restaurant, etc.)