Definition of "adamant" in English

adjective

1. (said of people and their conviction) Firm; unshakeable; unyielding; determined.

2. (of an object) Very difficult to break, pierce, or cut.

noun

1. An imaginary rock or mineral of impenetrable hardness; a name given to the diamond and other substances of extreme hardness.

   • As an adamant harder than flint have I made thy forehead …

2. An embodiment of impregnable hardness.

   • Actual life might seem to her so real that she could not detect the union of shadow and adamant that men call poetry.

3. (archaic) A lodestone.

4. (obsolete or historical) A substance that neutralizes lodestones.