For physical strength:
* fort (masculine) - This is the most common word for "strong" and applies to physical strength, power, and resilience.
* forte (feminine) - This word is the feminine form of "fort" and is used when referring to a woman or a feminine noun.
* puissant (masculine) - This word implies a powerful and imposing strength.
* puissante (feminine) - This word is the feminine form of "puissant".
For other meanings of "strong":
* solide - This word implies stability, firmness, and durability. It can refer to physical objects or concepts.
* épais - This word is used to describe something thick or dense, such as a wall or a book. It can also be used metaphorically to describe something strong or difficult to understand.
* vigoureux (masculine) - This word implies a vigorous, energetic, and healthy strength.
* vigoureuse (feminine) - This word is the feminine form of "vigoureux".
* robust - This word implies strength and resistance to damage or wear.
* intense - This word is used for things that are powerful or strong in feeling or effect.
* violent - This word implies a strong, forceful, and often destructive power.
Examples:
* Un homme fort: A strong man
* Une femme forte: A strong woman
* Un château puissant: A powerful castle
* Une boisson solide: A strong drink
* Un argumentaire vigoureux: A strong argument
* Un sentiment intense: An intense feeling
The specific word you choose will depend on the specific context of what you are trying to say.