soap

Boyd’s Bible Dictionary:

(sap, resin). The Hebrew word for soap implies any alkaline substance used for cleansing (Jer. 2:22; Mal. 3:2).

“Soap, Sope” From Concise Bible Dictionary:

Spoken of as used for cleansing the person, and as employed by the fuller (Jer. 2:22; Mal. 3:2). What its composition was is not now known.

“Sope” From Concise Bible Dictionary:

See SOAP.

Strong’s Dictionary of Hebrew Words:

Number:
1287 (find all occurrences in KJV Bible)
Transliteration:
boriyth
Phonic:
bo-reeth’
Meaning:
feminine of 1253; vegetable alkali
KJV Usage:
sope