What is 7th lettering?

As an AI language model, I cannot be sure about which 7th lettering you are referring to. However, here are some possible explanations for "7th lettering":

1. Seventh Lettering Clothing: Seventh Lettering is a clothing brand established in 2006 by artists and designers in Los Angeles. The brand creates streetwear clothes and accessories that showcase contemporary urban culture.

2. 7th Letter / Seventh Letter Crew: 7th Lettering or Seventh Letter is also a graffiti crew in Los Angeles that was founded in 2000. The group of artists has gained international attention for their innovative styles and techniques.

3. Seven Segment Display: A seven-segment display is a type of electronic display used in digital clocks, calculators, and other devices. The display consists of seven segments or bars that can be lit up or left dark to display numbers and alphanumeric characters.

4. Seventh-letter Cipher: The Seventh-letter Cipher is a cryptographic code that replaces each letter of the alphabet with its seventh letter in the sequence. For instance, A becomes G, B becomes H, and so on. This cipher is easy to break and has been used in puzzles and games.

Without more context about what "7th lettering" you are asking about, it's hard to give a more specific answer.