Heb. miphtan, probably a projecting beam at a higher point than the threshold proper (1 Samuel 5:4,5; Ezekiel 9:3; 10:4,18; 46:2; 47:1); also rendered "door" and "door-post."
'Asuppim, pl. (Nehemiah 12:25), rendered correctly "storehouses" in the Revised Version. In 1Chr 26:15,17the Authorized Version retains the word as a proper name, while in the Revised Version it is translated "storehouses."
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain, copy freely.
Easton, Matthew George. "Entry for 'Threshold'". "Easton's Bible Dictionary".