Ironhearted is a term used to describe someone who is emotionally tough and unyielding. There are several synonyms that can be used to describe someone with this kind of personality. For example, the word "unfeeling" means lacking in emotion or sensitivity. "Ruthless" describes someone who is merciless or unforgiving. "Cold-blooded" can also describe someone who is unemotional and indifferent towards the feelings of others. "Stoic" refers to a person who remains calm and unemotional, even in the face of adversity. Finally, "hard-hearted" is another term that can be used to describe someone who is tough-minded and unyielding when it comes to their emotions.