General confidence and self-assurance:
* Bravado: Bold and confident behavior, often intended to impress.
* Assurance: A confident and self-assured manner.
* Self-confidence: Belief in one's own abilities.
* Arrogance: Excessive pride and self-importance.
* Smugness: Self-satisfied, often to the point of being arrogant.
* Cockiness: Overconfident and arrogant.
Physical swagger:
* Strut: To walk with a proud and confident gait.
* Stroll: To walk with a relaxed and confident manner.
* Saunter: To walk leisurely and confidently.
Specific to a particular area:
* Panache: A flamboyant or stylish manner. (Often used in fashion)
* Mojo: An aura of success, charm, and attractiveness. (Used in music and popular culture)
Negative connotations:
* Boastfulness: To talk about oneself or one's achievements in a way that is intended to impress others.
* Pretentiousness: To try to appear more important or impressive than one really is.
* Braggadocio: Arrogant and boastful talk.
The best synonym for "swagger" will depend on the specific context in which it is used.