As used in philosophy
, in general, an object
is something that can have properties
. Hence a particular object is, basically, either a particular material body
or a particular mind
--or, on a neutral monist
view, a particular that can be viewed under both physical and mental aspects.
Symbols represent objects; how they do so, the map-territory relation, is the basic problem of semantics.
Objects are often treated as types of particulars, but occasionally, philosophers see fit to speak of abstract objects--Platonic forms would be an example.
Much, much more at objecthood