What is the longest word in the Bible?

MAHER-SHALAL-HASH-BAZ, a name (Isaiah 8:1)

https://en.wikipedia.org/wiki/Maher-shalal-hash-baz
http://www.bibleinfo.com/en/questions/bible-trivia-facts

"Righteousness" has 13 letters.

With most fonts, "commandments," with its 12 letters, actually takes up more space.

The two longest words in the Bible have 18 letters each.
MAHER-SHALAL-HASH-BAZ (Isaiah 8:1) is the name given to Isaiah's son, meaning "swift is booty, speedy is prey."
JONATH-ELEM-RECHO-KIM, which is found in the title of Psalm 56, is the name of a song and means "the silent dove of far-off places".

The second longest word in the Bible is CHU-SHAN-RISH-A-THA-IM (17 letters). It is first recorded in Judges 3:8 and it is the name of "the king of Mesopotamia" and means "the Ethiopian of double wickednesses".

There are eight 16-letter words:
BA-SHAN-HA-VOTH-JA-IR (Deuteronomy 3:14), COVENANTBREAKERS (Romans 1:31), EVILFAVOUREDNESS (Deuteronomy 17:1), KIB-ROTH-HAT-TA-A-VAH (Numbers 11:34), LOVINGKINDNESSES (Psalm 25:6), SE-LA-HAM-MAH-LE-KOTH (1 Samuel 23:28), UNPROFITABLENESS (Hebrews 7:18), CHE-PHAR-HA-AM-MO-NAI (Joshua 18:24).

The longest unhyphenated words in the Bible are COVENANTBREAKERS (Romans 1:31), EVILFAVOUREDNESS (Deuteronomy 17:1), LOVINGKINDNESSES (Psalm 25:6), UNPROFITABLENESS (Hebrews 7:18) (all 16 letters).



34 Therefore the name of that place was called Kib'roth-hatta'avah,
http://biblehub.com/numbers/11-34.htm


Isaiah 8

1 Moreover the LORD said unto me, Take thee a great roll, and write in it with a man's pen concerning Mahershalalhashbaz.
http://www.bibleinfo.com/en/questions/bible-trivia-facts

Not to be forgotten is Pocherethhazzebaim (18 letters) found in Ezra 2:57. However I've noted that some words may be slightly different in spelling in different Bible translations. This rendition is taken from the New World Translation of the Holy Scriptures.

Three words are tied for first place in the original Hebrew: "Uch'aliloteihem" ("And like their deeds"), "uch'to'avoteihen" ("and like their abominations"), both found in Isaiah and Jeremiah, and "v'ha'achashdarpanim" ("and the achasdarpanites/scribes"), found in chapter 8 of Esther. All words are 11 letters long in Hebrew.