Magka-ututang Dila

English Translation: Sucking each other's tongue

Actual Meaning: Best of friends; Deepest friends. This pertains to persons who are so close to one another that they even share their deepest secrets

Sample Sentence:

Tagalog:
Hindi ka maaaring magsabi kay John ng anuman laban kay Peter dahil silang dalawa ay magka-ututang dila.

English:
You must not tell John anything bad about Peter because they are the very best of friends.