1. Used especially of drugs or muscles that work together so the total effect is greater than the sum of the two (or more)
   - synergistic 
2. Capable of acting on or influencing each other
   - interactional

See also: interact, mutual, reciprocal

Encyclopedia: Interactive

• outdoors
• outdoorsman
• outdoorswoman
• outdoorsy
• outdraw
• outer
• outer boundary
• outer ear
• outer garment
• Outer Hebrides
• Outer Mongolia
• outer planet
• outer space
• outercourse
• outermost
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• outface
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• outfit
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