[count], 1 : the main subject that is being discussed or described in a piece of writing, a movie, etc. The quest for power is the underlying theme of the film. A constant theme in his novels is religion. The playwright skillfully brings together various themes. 2 a : a particular subject or issue that is discussed often or repeatedly, The growing deficit was a dominant theme in the election. b : the particular subject or idea on which the style of something (such as a party or room) is based, The party had a Hawaiian luau theme. The theme of the baby's room was zoo animals. [=the baby's bedroom was decorated with pictures of zoo animals], a theme party, 3 music, a : the main melody that is repeated in a piece of music, b : THEME SONG, They played the theme from/to the movie “Rocky.”, 4 US : a short piece of writing by a student on a particular subject : ESSAY, The students were assigned to write a theme on the person they admired most.