What “unique word” means in this count
Here “unique” means a case-insensitive exact word form that occurs once in the complete 66-book KJV corpus used by BibleAV—a hapax legomenon in this English text. It does not mean a word that appears in only one book but may repeat within that book, and it does not combine related forms. For example, a singular, plural, or older inflected spelling is counted separately if its letters differ.
The scan contains 789,629 word tokens, 12,747 distinct case-folded forms, and 4,022 forms occurring exactly once under this tokenisation. Letter sequences joined by an internal hyphen or apostrophe remain one token, while hyphens and apostrophes are not counted as letters. Supplied words shown in square brackets remain part of BibleAV’s searchable English text.
The three longest unique non-proper words
Covenantbreakers — 16 letters, Romans 1:31. Paul includes the word in a catalogue describing people who are “without understanding, covenantbreakers, without natural affection, implacable, unmerciful.” It is a plural noun for people who break covenants or solemn agreements.
Evilfavouredness — 16 letters, Deuteronomy 17:1. Israel must not sacrifice an animal containing a blemish or “any evilfavouredness.” In this context the word describes an objectionable defect or bad appearance that makes the animal unfit for sacrifice.
Unprofitableness — 16 letters, Hebrews 7:18. The writer speaks of the “weakness and unprofitableness” of the preceding commandment. The word describes its inability to bring the perfection discussed in the surrounding argument.
Why there is no one longest answer
All three words have sixteen alphabetic characters, and each appears once. Alphabetical ordering could place covenantbreakers first, but that would not make it longer than the other two. The accurate answer is therefore a three-way tie.
Several 16-letter names or place-names also occur once, including Bashan-havoth-jair, Chephar-haammonai, and Selahammahlekoth when punctuation is ignored. They are excluded because the question asks for words that are not proper nouns. At fifteen letters, ordinary one-time words include acknowledgement, administrations, bloodguiltiness, confectionaries, fellowdisciples, fellowprisoners, and prognosticators.
The shortest unique words: a 25-way tie
After proper names and common function words are removed, no eligible one- or two-letter word occurs exactly once. The minimum is three letters, shared by 25 ordinary words:
ado — Mark 5:39; ant — Proverbs 6:6; ash — Isaiah 44:14; asp — Isaiah 11:8; bee — Isaiah 7:18; boy — Joel 3:3; cab — 2 Kings 6:25; cor — Ezekiel 45:14; gap — Ezekiel 22:30; gay — James 2:3; hap — Ruth 2:3; hip — Judges 15:8; jot — Matthew 5:18.
leg — Isaiah 47:2; lid — 2 Kings 12:9; lop — Isaiah 10:33; maw — Deuteronomy 18:3; oar — Ezekiel 27:29; odd — Numbers 3:48; owe — Romans 13:8; rip — 2 Kings 8:12; rue — Luke 11:42; sap — Psalm 104:16; sue — Matthew 5:40; wen — Leviticus 22:22.
What some of the short words mean
Several are ordinary nouns: ant, ash, asp, bee, boy, gap, hip, leg, lid, oar, rue, and sap. Cab and cor are measures. Maw is the stomach of an animal; wen is a swelling or blemish; and jot is the tiny written mark in Jesus’ saying about the law.
Others preserve older English senses. Ado means disturbance or commotion in Mark 5:39. Ruth’s “hap” means what happened or befell her. The “gay clothing” of James 2:3 is fine or splendid clothing. “Lop” in Isaiah 10:33 means to cut off, while “rip” in 2 Kings 8:12 belongs to the violent prediction concerning women with child.
Why the two-letter forms are excluded
The only two-letter forms occurring once under this scan are Ed in Joshua 22:34 and Ir in 1 Chronicles 7:12. Ed is the name assigned to the altar as a witness, and Ir is a personal name in a genealogy. Both are proper nouns, so neither answers the question as posed.
One-letter forms such as a, I, and O occur many times and are not unique. Common function words are excluded from the short-word result even if a particular archaic form happened to occur once, because the aim is to identify lexical words rather than pronouns, articles, or interjections.
Why other counts may differ
The result is specific to BibleAV’s KJV 1769 text and its spelling. A different KJV edition may change punctuation, supplied-word formatting, compound words, or a small number of spellings. A modern translation necessarily produces a different vocabulary.
Results also change if a program strips hyphens before tokenising, treats every capitalised verse-opening word as a name, combines inflected forms, or defines “unique” as confined to one book rather than occurring once in the whole Bible. Stating the method is therefore part of the answer, not an incidental technical detail.