-shən ə lē, -shnəlē, -li adverb
: in a fractional manner : by a fraction : to the extent of a fraction
the stock had declined fractionally
: by fractions
squirming on his belly like a lizard, moving fractionally … one shoulder came forward, a pause, then the other — Alan Sullivan
: to a small or insignificant extent
the area had been only fractionally explored