anxiety

In most cases, 'anxiety' is used as an uncountable noun when describing a general feeling of worry (e.g., "too much anxiety"). When referring to specific types or clinical conditions, it can be treated as a countable noun (e.g., "she suffers from various anxieties"). Be careful with the third meaning: 'anxiety' does not always mean fear. When followed by "to" or "for," it often describes a strong, eager desire to achieve something.