File: mapping.json

{
    "settings": {
    "analysis": {
        "analyzer": {
            "en": {
                "tokenizer": "standard",
                "stopwords": "_english_",
                "filter": [
                    "lowercase",
                    "en_US",
                    "synonym",
                    "asciifolding",
                    "en_stemmer"
                ]
            },
            "synonym" : {
                "tokenizer" : "whitespace",
                "filter" : ["synonym"] 
            }
        },
        "filter": {
            "en_US": {
                "type": "hunspell",
                "locale": "en_US",
                "dedup": true
            },
            "synonym" : {
                "type" : "synonym", 
                "synonyms_path" : "analysis/synonym.txt",
                "tokenizer" : "whitespace" 
            },
            "en_stemmer" : {
                "type" : "stemmer",
                "name" : "english"
            }
        }
    }
},
    "mappings": {
        "knowledgebase": {
            "properties": {
                "question": {
                    "type": "text",
                    "analyzer" : "en"
                },
                "answer": {
                    "type": "text",
                    "analyzer" : "en"
                }
            }
        }
    }
}