Segûllâh (סְגֻלָּה, Strong's #5459), “possession.” Cognates of this word appear in late Aramaic and Akkadian. This word occurs only 8 times.
Cegullah signifies “property” in the special sense of a private possession one personally acquired and carefully preserves. Six times this word is used of Israel as God’s personally acquired (elected, delivered from Egyptian bondage, and formed into what He wanted them to be), carefully preserved, and privately possessed people: “Now therefore, if ye will obey my voice indeed, and keep my covenant, then ye shall be a peculiar treasure [NASB, “possession”] unto me above all people: for all the earth is mine” (Exod. 19:5—first occurrence).