Rock hard
Synonyms for Rock hard
- flintyhard like rock
- impenetrablehard like rock
- indestructiblehard like rock
- unbreakablehard like rock
- adamantinehard like rock
- rock-hardhard like rock
- tough
- cruel
- unyielding
- dense
- ferric
- ferrous
- implacable
- indomitable
- inexorable
- insensible
- obdurate
- relentless
- robust
- stubborn
- unbending
- thick
- steel
- immovable
- heavy
- adamant
- rigid
- determined
- hard as nails
- steely
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