In my dictionary, concrete means "existing in fact and not merely as a possibility", for example, concrete evidence. I was wondering if concrete in that sense is same as specific?
Concrete and specific mean very different things, although in some circumstances they may both be applied to communicate somewhat similar meanings.
Specific is approximately synonymous with particular or individual; its antonym is usually general. A general property or attribute applies to all members of a class; a specific property or attribute applies to only some members or one member of the class.
Concrete is approximately synonymous with tangible or material; its antonym is usually abstract. An abstract entity has no physical existence, it is a mental construction, an idea; but a concrete entity is, in some sense, present to the senses.
The overlap arises when we are contrasting a physical ‘thing’ with the non-physical ‘class’ or ‘category’ to which it belongs. For instance, ‘human’ signifies those general qualities which are shared by all individual persons, or the abstract quality of being human, a member of the class homo sapiens; but an individual person is both specific, distinguishable from every other person, and concrete, possessing physical existence;.