hard-shell

adj hard-shell

• accepted — Accepted ideas are agreed by most people to be correct or reasonable.
• accustomed — If you are accustomed to something, you know it so well or have experienced it so often that it seems natural, unsurprising, or easy to deal with.
• chronic — A chronic illness or disability lasts for a very long time. Compare acute.
• deep-rooted — Deep-rooted means the same as deep-seated.
• deep-seated — A deep-seated problem, feeling, or belief is difficult to change because its causes have been there for a long time.