A primitive root; to store up -- (lay up in) store, + (make) treasure(-r).
Englishman's Concordance
1) to store up, save, lay up 1a) (Qal) to store up, make treasurer 1b) (Niphal) treasured Part of Speech: verb A Related Word by BDB/Strong’s Number: a primitive root Same Word by TWOT Number: 154
Brown-Driver-Briggs
[אָצַר] verblay up, store up (Mishna id., Aramaic אֲצַר, , Arabic confine, restrict) —
Niph`alImperfectיֵאָצֵר be stored up, of the merchandise of Tyre Isaiah 23:18.
Hiph`ilImperfectוָאוֺצְרָה (compare Köi, 391) (denominative from אוֺצָר) Nehemiah 13:13and I appointed treasurer, followed by accusative of person + עַלאֿוֺצָרוֺת.
2 Kings 20:17 HEB:בְּבֵיתֶ֗ךָ וַאֲשֶׁ֨ר אָצְר֧וּ אֲבֹתֶ֛יךָ עַד־ NAS: and all that your fathers have laid up in store to this KJV: and that which thy fathers have laid up in store unto this day, INT: house after have laid your fathers against
Nehemiah 13:13 HEB: וָאוֹצְרָ֣ה עַל־ א֠וֹצָרוֹת NAS: of the storehouses I appointed Shelemiah KJV:And I made treasurers over the treasuries, INT:appointed charge of the storehouses
Isaiah 23:18 HEB:לַֽיהוָ֔ה לֹ֥א יֵֽאָצֵ֖ר וְלֹ֣א יֵֽחָסֵ֑ן NAS: to the LORD; it will not be stored up or hoarded, KJV: to the LORD: it shall not be treasured nor laid up; INT: to the LORD not will not be stored or hoarded
Isaiah 39:6 HEB:בְּבֵיתֶ֗ךָ וַאֲשֶׁ֨ר אָצְר֧וּ אֲבֹתֶ֛יךָ עַד־ NAS: and all that your fathers have laid up in store to this KJV: and [that] which thy fathers have laid up in store until this day, INT: house after have laid your fathers against
Amos 3:10 HEB:נְאֻם־ יְהוָ֑ה הָאֽוֹצְרִ֛ים חָמָ֥ס וָשֹׁ֖ד NAS: the LORD, these who hoard up violence KJV: the LORD, who store up violence INT: declares the LORD hoard violence and devastation
, Arabic 
confine, restrict) —