The term 'feed on' can be defined by the following crossword solutions: INGEST (6 letters), EAT (3 letters), NURTURE (7 letters), PARTAKE (7 letters), and PASTURE (7 letters). Ingesting is the process of taking in food or other substances into the body, while eating is the act of consuming food. Nurturing is the act of providing care and support for something or someone, while partaking is to take part in something. Lastly, pasturing is the act of grazing animals on land covered with grass or other vegetation. All of these terms can be used to describe the act of feeding on something.