SELECT words.id, words.definition
FROM stock 
  JOIN languages ON (stock.languageID = languages.id)
  JOIN stockmatch ON (stockmatch.stockID = stocks.id)
  JOIN words ON (stockmatch.wordID = words.word_id)
  JOIN types ON (words.typeID = types.id)
WHERE stock.word = :stock_word
  AND language.name = :language_name
  AND type.name = :type_name