Panlexicon
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Panlexicon is a unique thesaurus that provides a quicker and more intuitive process for finding the words you want. Learn more about Panlexicon.

  • adamant
  • adamantine
  • cast-iron
  • certain
  • constant
  • dogged
  • dour
  • durable
  • enduring
  • faithful
  • firm
  • fixed
  • flinty
  • fundamentalist
  • grim
  • hard
  • hard-core
  • harsh
  • hidebound
  • immovable
  • immutable
  • implacable
  • impliable
  • inclement
  • inelastic
  • inescapable
  • inexorable
  • inflexible
  • intractable
  • intransigent
  • iron
  • ironbound
  • ironclad
  • ironhanded
  • irreconcilable
  • lasting
  • loyal
  • merciless
  • muscle-bound
  • obdurate
  • obstinate
  • orthodox
  • persistent
  • procrustean
  • purist
  • puristic
  • puritan
  • puritanic
  • relentless
  • resolute
  • rigid
  • rigorist
  • rigoristic
  • rigorous
  • rockbound
  • rock-ribbed
  • set
  • severe
  • single-minded
  • stable
  • staunch
  • steadfast
  • steady
  • steely
  • stern
  • stiff
  • straightlaced
  • straitlaced
  • strict
  • stringent
  • stubborn
  • tenacious
  • tough
  • unaffected
  • unalterable
  • unavoidable
  • unbending
  • unchangeable
  • uncompromising
  • undeflectable
  • ungiving
  • unmoved
  • unrelenting
  • unswerving
  • unyielding
Panlexicon is a unique thesaurus that provides a quick and intuitive process for finding the words you want. Learn more about Panlexicon.
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