Isogram
A word in which no letter repeats — also called a heterogram in some usages.
Why it matters
Isograms are useful constraints in puzzle construction and in cipher design. The longest single-word isograms in English are roughly 15 letters.
Examples
- uncopyrightable, dermatoglyphics, subdermatoglyphic
Best practices
- Use isograms as drills for spotting repeated letters
- Watch for isograms when constructing puzzles or cryptograms
Frequently asked questions
Is isograms important for beginners?
isograms matters at every skill level, but beginners benefit most from understanding the basic concept rather than every edge case. Building a working mental model of isograms early prevents recurring mistakes in word play.
How do I practice isograms effectively?
Practice isograms through deliberate isolation drills first, then through integrated play. Two short focused sessions per week will yield steady measurable gains within a month.
Where can I read more about isograms?
Cross-reference the related terms below and explore the academy articles linked from this entry; both provide deeper applied context for isograms.
Related terms
Heterogram
A word or phrase in which no letter appears more than once.
TermPalindrome
A word, phrase, or sequence that reads the same forwards and backwards.
TermWord Pattern
A recurring arrangement of letters, sounds, or structure across multiple words.
Written and reviewed by
Keiron Brown, Psy.D.
Clinical Psychologist · Founder & Editor, WordRushTools
Relationale LLC · 5530 S. University Drive, 3212, Davie, FL 33328
Keiron Brown, Psy.D., is a clinical psychologist and the founder of Relationale LLC, which publishes WordRushTools. His doctorate is in psychology, which is directly relevant to the site's material on vocabulary learning, memory and practice; the Scrabble, crossword and solver content rests on published word lists and reference works, not on clinical expertise.
Last reviewed: by Keiron Brown. Reference and strategy pages are reviewed annually, and sooner where the underlying word lists change.
Not a clinical or educational service: Nothing on WordRushTools is intended or designed to be, or to replace, mental health services, psychological assessment or treatment, diagnosis, therapy, or educational or special-education services. Word games are not a treatment for any condition, and we make no claim that playing them prevents cognitive decline.