I-adjective (keiyoushi)
hard; solid; tough
esp. 固い and 堅い for wood, 硬い for metal and stone
卵は硬くゆでてください。Boil the eggs hard. stiff; tight; wooden; unpolished (e.g. writing)
strong; firm (not viscous or easily moved)
safe; steady; honest; steadfast
certain; assured; highly likely
of a predicted outcome
obstinate; stubborn
bookish; formal; stuffy
solid (shape or stones)
Go (game)
Also written 固い【かたい】、堅い【かたい】、緊い【かたい】