Similar Meaning:
* Self-control: This emphasizes the ability to restrain impulses and desires.
* Willpower: This focuses on the mental strength to resist temptations and pursue goals.
* Self-restraint: Similar to self-control, but with a focus on limiting oneself.
* Self-mastery: This suggests a higher level of control over oneself, including thoughts, emotions, and actions.
* Perseverance: This highlights the ability to continue working towards a goal despite challenges.
* Grit: This describes the combination of passion and perseverance needed for achieving long-term goals.
More informal:
* Determination: A strong desire to achieve something.
* Focus: A concentrated effort on a specific task or goal.
* Discipline: This can be used as a synonym for self-discipline, especially in a more general sense.
The best word to use will depend on the specific context and the nuance you want to convey.