Having a very high hardness. / (not comparable, mineralogy) Having a hardness between that of boron nitride and diamond.

(motorsports) Ellipsis of superhard tyre. (A tyre whose compound is harder than hards, and therefore harder than mediums, softs.)

plural of superhard

(transitive) To make superhard.

simple past tense and past participle of superharden

present participle of superharden

Third-person singular simple present indicative form of superharden