The Extended Synonym Dictionary module replaces words with groups of their synonyms, and so makes it possible to search for a word using any of its synonyms. It accepts the following options: KEEPORIG controls whether the original word is included, or only its synonyms. Default is 'true'. RULES is the base name of the file containing the list of synonyms. This file must be in $(prefix)/share/tsearch_data/, and its name must end in ".rules" (which is not included in the RULES parameter). The rules file has the following format: Each line represents a group of synonyms for a single word, which is given first on the line. Synonyms are separated by whitespace: word syn1 syn2 syn3 Sharp ('#') sign is a comment delimiter. It may appear at any position inside the line. The rest of the line will be skipped. Look at xsyn_sample.rules, which is installed in $(prefix)/share/tsearch_data/, for an example. mydb=# SELECT ts_lexize('xsyn','word'); ts_lexize ---------------- {word,syn1,syn2,syn3) Change dictionary options: mydb# ALTER TEXT SEARCH DICTIONARY xsyn (KEEPORIG=false); ALTER TEXT SEARCH DICTIONARY