The song is M-O-T-H-E-R
http://tinchicken.com/holidays/momday/mom2.htm


A word that means the world to me
M is for the million things she gave me
O means only that she's growing old
T is for the tears she shed to save me
H is for her heart of purest gold
E is for her eyes, with love-light shining
R means right, and right she'll always be

Put them all together, they spell "MOTHER"

A word that means the world to me