While acquisitive is a useful synonym of the likes of greedy and avaricious, it's relatively unknown compared to its more popular lexical relations, acquire and acquisition. The former of that pair is most often used to mean "to get as one's own," as in "skills acquired through practice"; the latter refers either to the act of acquiring something, as in "the acquisition of skills," or to something or someone acquired or gained, as in "the museum's recent acquisitions." All three have as their ultimate source the Latin word acquīrere, meaning "to acquire." While acquire and acquisition have both been in use since the 15th century, acquisitive is a bit younger. The word has a somewhat rare use meaning "capable of acquiring" that dates to the late 16th century, but its "greedy" meaning dates only to the early 19th century.