The sensus plenior is that additional, deeper meaning, intended by God but not clearly intended by the human author, which is seen to exist in the words of a biblical text (or group of texts, or even a whole book) when they are studied in the light of further revelation or development in the understanding of revelation.
Raymond E. Brown, The Sensus Plenior of Sacred Scripture (Baltimore: St. Mary's University, 1955), 92
Raymond E. Brown, The Sensus Plenior of Sacred Scripture (Baltimore: St. Mary's University, 1955), 92