An alternate phrase to "babe", "baby" "honey" etc, but with the same loving connotations.
Typically used by boys in a love hate relationship, or as an insult with a sweet filling (meaning) inside.
Alternatively used by boys who can't express their true feelings to girls.
G: Hey guess what, I passed my driving test
B: Aww I'm so proud of my lil bighead ❤️