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1. The strength of a solution; number of molecules of a substance in a given volume
    
2. The spatial property of being crowded together
   - density, denseness, tightness, compactness
    
3. Strengthening the concentration (as of a solute in a mixture) by removing diluting material
    
4. Increase in density
    
5. Complete attention; intense mental effort
   - engrossment, absorption, immersion
    
6. Bringing together military forces
    
7. Great and constant diligence and attention
   - assiduity, assiduousness

Derived forms: concentrations

Type of: assemblage, assembly, attention, diligence, gathering, increase, industriousness, industry, property, spacing, spatial arrangement, strengthening

Antonym: dilution

Encyclopedia: Concentration