After some googling around both seem to be interchangable words, where we speak of tying the spatial info of a real place and storing in database.
But still I am not satisfied, there should be some major differences. Also are there any tools in Oracle Spatial suite for this to carry out.
Answer
To easily understand these terms, let's use example of an online mapping service (say Google maps, Mapquest etc.)
When you type an address or a placename in the searchbox and in return the map shows a marker at the place. The process of associating an address or a placename with coordinates on the map is called Geocoding. In a spatial database this is done as a point layer with name of the place as an attribute to the point location. This is one way of geocoding. For addresses, the associated coordinates are not saved in a database directly, but computed using a method called linear referencing. (Thus the confusion between the terms geo-referencing and linear-referencing ) The start and end addresses along a line segment are saved and intermediate addresses are interpolated and the coordinates are calculated. As for your question, Oracle spatial has linear referencing support. http://docs.oracle.com/html/A88805_01/sdo_lrsa.htm
In some online mapping service, you may have seen satellite imagery. When these images are captured from a satellite or an airplane, they are just plain images, like photographs. But to display these images on a map, they need to be associated with map coordinates. This process is called GeoReferencing. Once the image is associated with the map coordinates it can be overlaid on top of street maps. For georeferencing, you can use a GIS software such as ArcGIS or QGIS to georeference an otherwise un-referenced image or scanned maps, and load them into Oracle Spatial.
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