identical

(noun, adjective)

adjective

1. exactly alike; incapable of being perceived as different

- rows of identical houses

- cars identical except for their license plates

Similar word(s): same, indistinguishable

2. being the exact same one; not any other:

- this is the identical room we stayed in before

Similar word(s): same, selfsame, very

3. (of twins) derived from a single egg or ovum

- identical twins are monovular

Similar word(s): monovular

4. having properties with uniform values along all axes

Similar word(s): isotropic, isotropous

5. coinciding exactly when superimposed

- identical triangles

Similar word(s): congruent, superposable

noun

1. (usually pluralized, chiefly philosophy) Something which has exactly the same properties as something else.

2. An identical twin.