There are several synonyms for the word "sixteenth part." One common synonym is "sixteenth," which refers to any one of 16 equal parts. Another synonym is "hexadecime," which comes from the Latin word "hexadecimus" meaning "sixteenth." "Sextant" is another synonym that is used mainly in navigation and astronomy to refer to one-sixteenth of a circle. Other synonyms include "fraction," "division," "segment," and "piece." Each of these words can be used interchangeably to refer to a fraction or part that is equivalent to one-sixteenth. Regardless of which synonym you choose to use, the meaning remains the same - one-sixteenth of a whole.