The term 'fill with joy' can be expressed in four different ways, each with a different number of letters. The first is 'ELATE' with five letters, which means to fill with joy or exalt. The second is 'ENRAPTURE' with nine letters, which means to fill with joy or delight. The third is 'GLADDEN' with seven letters, which means to fill with joy or cheer. The fourth is 'REJOICE' with seven letters, which means to fill with joy or celebrate. All of these terms describe the same feeling of being filled with joy.