Meaning
A simple yellow face with a gently downturned mouth, the mirror image of 🙂. Literally it is a slight frown.
It expresses mild sadness or disappointment, like plans being cancelled or a favourite shop closing early. It is softer than ☹️, which has a deeper frown. Pair with 😔 when the mood drops further. Example: “Rain again, so no picnic this weekend 🙁”.