F4I1F4T1E1E1N1T1H4
18 points
FIFTEENTH is validvalid
one of fifteen equal parts [n FIFTEENTHS]
number fifteen in sequence [adj FIFTEENTHLY] / one of fifteen equal parts [n -S]
one of fifteen equal parts [n FIFTEENTHS]
number fifteen in sequence [adj FIFTEENTHLY] / one of fifteen equal parts [n -S]