Hi, Let's say I have this synonyms entry : b c => ok
My configuration (index time) : 1. WhitespaceTokenizerFactory 2. WordDelimiterFilterFactory with catenateWords="0" 3. SynonymFilterFactory The input : "a/b c" produce (one line per tokenizer/filter) 0:"a/b", 1:"c" 0:"a", 1:"b", 2:"c" 0:"a", 1:"ok" So everything is ok, now if I set catenateWords to "1", the same input produce : 0:"a/b", 1:"c" 0:"a", 1:"b", 1:"ab", 2:"c" 0:"a", 1:"b", 1:"ab", 2:"c" The synonym filter doesn't match entry because of the extra token "ab" between "b" and "c". To my mind the synonym should be triggered when a token "b" and a token "c" are separate by one position (which is still the case in the second example). Is there any way to make the second example work ? Jean-Marc