Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
ni-hard is a noun meaning "cast iron to which nickel has been added to make it resist abrasion". It carries one recorded sense.
cast iron to which nickel has been added to make it resist abrasion
Definitions, synonyms and semantic relations for ni-hard come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.