This article is from the Puzzles FAQ, by Chris Cole chris@questrel.questrel.com and Matthew Daly mwdaly@pobox.com with numerous contributions by others.
What exceptional words turn into other words by transposition of letters?
language/english/spelling/operations.on.words/transposition.s
longest reversal DESSERTS,STRESSED (8)
longest well-mixed transposal
CINEMATOGRAPHER, MEGACHIROPTERAN (15)
longest transposition list
APERS, APRES, ASPER, PARES, PARSE, PEARS, PRASE, PRESA, RAPES, REAPS, SPARE,
SPEAR (12)
ANGRIEST, ANGRITES, ASTRINGE, GAIRTENS, GANISTER, GANTRIES, GRANITES,
INGRATES, RANGIEST, TEARINGS (10) [SATING(ER), SIGNATE(R), TANGIER(S) (3)]
ANORETICS, ATROSCINE, CANOTIERS, CERTOSINA, CONARITES, CREATIONS, REACTIONS,
TRICOSANE (8)
transposition with deletion, insertion, or substitution
longest well-mixed transdeletion
SONOLUMINESCENCES, UNECONOMICALNESSES (17/18)
longest word transdeletable to a single letter
CONCENTRATIONS-CONSTERNATION-CONTORNIATES-TRANSECTION-
STENTORIAN-TRANSIENT-ENTRAINS-NASTIER-ASTERN-TEARS-SATE-TEA-AT-A (14)
longest Baltimore transdeletion (word transdeletable on every letter)
IDOLATERS: DELATORS, SOTERIAL, DILATERS, ASTEROID,
STOLIDER, SOREDIAL, DILATORS, DIASTOLE, TAILORED (9)
shortest word that cannot be transadded to another word SYZYGY (6)
longest well-mixed transubstitution
MICROELECTROPHORESIS, SPECTROCOLORIMETRIES (20)
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Unless noted otherwise, all words occur in Webster's Third New International
Dictionary, Merriam-Webster, Springfield, MA, 1961.
 
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