steady; sound; stable; safe (e.g. business); reliable; trustworthy; solid
堅実な生き方を心がけている。
I try to live in a steady, grounded way.
堅実な経営で会社が長年続いてきた。
Sound management has kept the company going for many years.
派手さより堅実さを重視して投資先を選んだ。
I chose investments valuing reliability over flashiness.