attention-deficit hyperactivity disorderatˌtention-ˌdeficit hyperacˈtivity disˌorder (also attention-deficit syndrome) noun [uncountable] medical (abbreviation ADHD) 
a medical condition that especially affects children. It causes them to be too active and to be unable to pay attention or be quiet for very long.
a medical condition that especially affects children. It causes them to be too active and to be unable to pay attention or be quiet for very long.- secretiveness
- secretly
- secret police
- secret service
- sect
- sectarian
- sectarianism
- section
- sectional
- Section Eight
- sector
- sectoral
- secular
- secularism
- secularist
- secularization
- secularize
- secure
- securely
- Securities and Exchange Commission
- Securities and Investments Board
- security
- security blanket
- security clearance
- Security Council