The get mapping API allows to retrieve mapping definition of index or index/type.
$ curl -XGET 'http://localhost:9200/twitter/tweet/_mapping'
The get mapping API can be used to get more than one index or type mapping with a single call. General usage of the API follows the following syntax: host:port/{index}/{type}/_mapping where both {index} and {type} can stand for comma-separated list of names. To get mappings for all indices you can use _all for {index}. The following are some examples:
$ curl -XGET 'http://localhost:9200/twitter,kimchy/_mapping'
$ curl -XGET 'http://localhost:9200/_all/tweet,book/_mapping'
If you want to get mappings of all indices and types then the following two examples are equivalent:
$ curl -XGET 'http://localhost:9200/_all/_mapping'
$ curl -XGET 'http://localhost:9200/_mapping'