From shabar; the orifice of the womb (from which the fetus breaks forth) -- birth, breaking forth.
see HEBREW shabar
H4866. mishbar
or mashber מַשְׁבֵּר noun [masculine] place of breach, i.e. mouth of womb; — עַדמֿ בָנִים ׳בָּאוּ לְלֵדָה אַיִן וְכֹחַ 2 Kings 19:3 = Isaiah 37:3 (figurative of helplessness); construct בָּנִים מִשְׁבַּר Hosea 13:13 (figurativeof opportunity).