Synonyms for Hard shell:

• adj.

  •confirmed (adjective)
  • valid,
  • worn,
  • Hard-shell.
  •hard-shell (adjective)
  • inured,
  • inveterate,
  • settled,
  • entrenched,
  • Val,
  • hardened,
  • firmly established,
  • staid,
  • ingrained,
  • irradicable,
  • ineradicable,
  • set,
  • deep-rooted,
  • deep-seated,
  • fixed,
  • accustomed,
  • long-established,
  • proved,
  • Habituated,
  • dyed-in-the-wool,
  • chronic,
  • seasoned.
  •harsh (adjective)
  • grim,
  • unrelenting,
  • punitive,
  • cussed,
  • ungracious,
  • gruff,
  • mean,
  • pitiless,
  • brutal,
  • unpleasant,
  • hard-boiled,
  • sharp,
  • discourteous,
  • hard-nosed,
  • rude,
  • cruel,
  • comfortless,
  • bitter,
  • austere,
  • stringent,
  • unfeeling,
  • relentless,
  • wicked,
  • uncivil,
  • stern,
  • dour,
  • unkind,
  • hairy,
  • severe,
  • tough,
  • ruthless,
  • hard.
  •headstrong (adjective)
  • mulish,
  • determined,
  • intractable,
  • imprudent,
  • Pig-headed,
  • impulsive,
  • willful,
  • obstinate,
  • heedless,
  • foolhardy,
  • froward,
  • ungovernable,
  • unyielding,
  • refractory,
  • rash,
  • unruly,
  • bullheaded,
  • perverse,
  • hard-core,
  • contrary,
  • strong-minded,
  • locked-in,
  • murder,
  • reckless,
  • uncontrollable,
  • self-willed,
  • mule.
  •stern (adjective)
  • inexorable,
  • inflexible,
  • harsh,
  • mortified,
  • rough,
  • ascetic,
  • hardheaded,
  • strict,
  • rigid,
  • stiff-necked,
  • frowning,
  • astringent,
  • rigorous,
  • steely,
  • flinty,
  • unsparing,
  • forbidding,
  • stubborn,
  • by the book,
  • hang-tough,
  • hard-line,
  • implacable,
  • disciplinary.

• n.

  •thick skin (noun)
  • imperviousness,
  • numbness,
  • armor,
  • apathy.

• Other synonyms:

  •adj.
  • accepted.
  •n.
  • callousness,
  • thick skin,
  • unfeelingness,
  • elephant skin,
  • formidable defenses,
  • rhinoceros hide,
  • thick hide,
  • thick shell.

Antonyms for Hard shell:

• adj.

  • confirmed
    sporadic, infrequent, unconfirmed, undecided, uncommitted, indefinite.
  • harsh
    gentle, tolerant, good, flexible, friendly, pleasing, pleasant, merciful, agreeable, facile, soft, peaceful, kind, nice, cheerful, wonderful, bland, smooth, polite, mild, calm, sympathetic, considerate, inexact, giving, easy, compassionate, courteous.
  • headstrong
    obedient, submissive, moderate, docile.
  • stern
    light, lenient, funny, smiling, yielding.