The porn video tag "big-tit-trans" has three main components:
1. Big tit: This refers to the presence of women with large breasts, a popular category in adult content. These videos often showcase scenes where the actresses have significant breast size and are enjoyed by viewers who appreciate this particular physical feature.
2. Trans: In this context, "trans" is short for transgender, which means that the video may include performers who are transsexual or transgender. This category can encompass a wide range of content involving both pre- and post-operative trans individuals as well as cisgender actors.
So, this tag indicates a porn video featuring large-breasted trans women or men with large breasts. The combination of these characteristics creates a specific niche within the adult industry that caters to viewers who are interested in both big breasts and transgender content.