King James Bible
King James Version (KJV)
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Or pitrah {pit-raw'}; from patar; a fissure, i.e. (concretely) firstling (as opening the matrix) -- firstling, openeth, such as open.
see HEBREW patar
H6363. peter
מֶּ֫טֶר noun [masculine] that which separates, first opens; — construct, ׳מּ רֶחֶם i. e. firstborn, of man and beast, Ezekiel 20:26; Exodus 13:12, 15; 34:19; Numbers 18:15; appositive בְּכוֺר Exodus 13:2; Numbers 3:12; רֶחֶם omitted Exodus 13:12-13, 34:19-20,.
[מִּטְרָה] noun feminine id., כָּלרֶֿחֶם מִּטְרַת Numbers 8:16.