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1. Exactly alike; incapable of being perceived as different
   "rows of identical houses"; "cars identical except for their licence plates";
   - indistinguishable
    
2. Being the exact same one; not any other:
   "this is the identical room we stayed in before";
   - selfsame, very
    
3. (of twins) derived from a single egg or ovum
   "identical twins are monovular";
   - monovular
    
4. (physics) having properties with uniform values along all axes
    
5. Coinciding exactly when superimposed
   "identical triangles";
   - superposable

See also: congruent, isotropic, isotropous, same

Antonym: fraternal

Encyclopedia: Identical