bit by bit, by degrees, by inches, by inchmeal, by slow degrees, by stages, consecutively, degreewise, drop by drop, gradatim, grade by grade, gradually, hand running, hierarchically, in Indian file, in a chain, in a line, in a row, in a series, in column, in file, in order, in sequence, in series, in single file, in succession, in turn, inch by inch, inchmeal, little by little, progressively, running, sequentially, serially, seriatim, slowly, successively, turn about