Sentence:  She had quarreled with Lucien , she had resisted his demands for money - and if she died , by the provisions of her marriage contract , Lucien would inherit legally not only the immediate sum of gold under the <WSD>floorboards</WSD> in the office , but later , when the war was over , her father 's entire estate . 
Meaning of the word marked with <WSD> tags:  a board in the floor