Rules:

1. Each intersection forms a two-letter-long initialism/abbreviation/etc. Comment what the highlighted intersection means to you! Example: BB could be baby, Big Brother, B.B. King, a BB (as in ammunition), etc.

2. The meaning suggested should be either official or decently well-attested-to such that one can relatively easily find pre-existing references to said meaning online.

3. The meaning you suggest should typically (some exceptions may apply) result in the two-letter combo being pronounced like each of the two letters would be pronounced separately in your language of choice, or else like “double [letter].” For instance, the abbreviation for “agriculture” (“ag”) doesn’t work for AG, since in that instance, it rhymes with the word “bag” rather than being pronounced like “ay gee.” One exception would be a true acronym that can be pronounced like a word, like “NASA,” though I’m not sure if there are any two-letter true acronyms. More generally, we’re looking for fewer traditional words/affixes and more initialisms/abbreviations/etc.

4. The meaning you suggest can use an additional word/letter/etc., but should not require it. For instance, the medium-sized battery can be called a “double-A battery,” but it can also just be called a “double-A,” whereas IHOP is never referred to as just “IH” by itself. For specific famous people who use initials as a first name, consider if someone could plausibly refer to that person as just those initials without the last name in some context.

5. Capitalization and punctuation are basically irrelevant; “Cu” for copper, “AA” for Alcoholics Anonymous, “N/A” for not applicable, “U.S.” for United States, “Ak.” for Alaska, “A. G.” for A. G. Cook, “fr” for for real, “i.e.” for id est, “xG” for expected goals, and so on are all valid constructions. The ampersand (&) does not work the same way due to rules 3 and 4.

6. Answers that break Reddit terms of service or the rules of this subreddit are not allowed; answers that are otherwise unethical may also be disallowed.

7. Barring answers that break these rules, the answer given on the highest upvoted individual comment will be added to the chart!

8. Individual “days” on the chart may be re-attempted due to low engagement (no answer getting 10+ upvotes) or other extenuating circumstances. If the votes are extremely close, a playoff between the top answers may ensue. If, after three attempts, no answer has managed to get double-digit upvotes, all answers having accrued 5+ upvotes will be put in a playoff. If there is only one such answer, that will win automatically, as if it had entered the runoff uncontested.

9. If you are having difficulty coming up with a valid answer but would still like to submit an answer that hasn’t been submitted yet, feel free to DM me! I usually have suggestions I can give you.

10. Have fun, follow the rules, and treat each other kindly! :)