- immovable
- unshakeable
- unwavering
- inflexible
- resolute
- uncompromising
- determined
- resolved
- rigid
- firm
- unswerving
- steadfast
- unrelenting
- stubborn
- unbending
- unyielding
- inexorable
- obdurate
- dead set
- intransigent
- strong-willed
- iron-willed
- rock-ribbed
- steely
- indurate
- stiff-necked
Example Sentences of Adamant
1. She remained adamant about her decision.
2. He was adamant in his beliefs.
3. They were adamant on starting early.
4. She’s adamant that it’s the truth.