A tree hugger is someone who loves and respects nature, often to the point of activism. The crossword solutions for the term 'tree hugger' are MOSS (4 letters), BOA (3 letters), BARK (4 letters), VINE (4 letters), and DRUID (5 letters). These words all relate to nature and the environment, with MOSS being a type of plant, BOA being a type of snake, BARK being the outer layer of a tree, VINE being a type of climbing plant, and DRUID being an ancient Celtic priest.