Critical or Critically may refer to:

• Critical, or critical but stable, medical states
  • Critical, or intensive care medicine
• Critical juncture, a discontinuous change studied in the social sciences.
• Critical Software, a company specializing in mission and business critical information systems
• Critical theory, a school of thought that critiques society and culture by applying knowledge from the social sciences and the humanities
• Critically endangered, a risk status for wild species
• Criticality (status), the condition of sustaining a nuclear chain reaction