Most dictionaries use a similar format, which is: The word, the pronuciation(s), the part(s) of speech (i.e. noun, verb), etymology of the word, and 1 or more numbered defintions with occational subdivisions (usually lower case letters).  It is the numbered defintions that cause problems in discussions.  When a dictionary entry has more than 1 meaning or sense, it means that the senses are different enough from each other to have a different meaning.  If the meanings are only slightly different but related, it will usually be put in a subset of the same number.  Here is an example from Merriam-Webster (http://www.merriam-webster.com/dictionary/light):

¹light