From مُشْتَرٍ(muštarin, “buyer, seller”), from the root ش ر ي(š r y) with the original semantic sense of bringing of goods or commodities (to be exchanged). This renders the title to mean "the bringer of goods", "provider of commodities", or "supplier of fortunes"; parallel with the planet's other names also denoting fortune and its auspicious nature.
Alternatively from the root ش ر ي(š r y) in the sense of "being persistent", "to be reliable"; possibly parallel with the title صَدِيق(ṣadīq) and Hebrewצֶדֶק(tzédek), which however can also be interpreted as "charitable", "giving", or "honoring".
Possible distant relation to Akkadian𒀭𒈪𒁲𒊑(mīšāru, “uprightness; god personifying justice”) and Ugaritic𐎎𐎌𐎗(mšr, “righteousness”), cognate with Hebrewיָשָׁר(yashár, “upright, right, correct”) and يَسْر(yasr). The root ي س ر(y s r) also however denotes "to procure goods easily", "to be or grow rich", "to live in affluence or ease", "to have good fortune".