Below you'll find a brief glossary that explains the basic and most frequently appearing concepts/memes on the Nico Nico Douga platform. For those interested in what this platform is, refer to our article on the subject: "Nico Nico Douga – Japan's Answer to YouTube".

Glossary:

1. Namanushi (生主) - Live broadcast; a short form of 生放送主, meaning the person conducting the live broadcast.

2. WWWWWW - Denotes laughter; the Japanese version of our "hahaha".

3. BBA - Abbreviation for "babba", which means an older woman or grandmother.

4. 888888888 - Indicates applause; "pachi pachi" is the Japanese onomatopoeia for clapping.

5. KP - Short for "kanpai", meaning a toast or "cheers".

6. こy - A mix of the words "kowaii" (scary in Japanese) and "scary".

7. おk - Means "Okay".

8. おこk - Another way to write "OKOK".

9. ひy - Short for "hiwai", meaning "indecent" or "crazy".

10. Arashi (荒らし) - Indicates an internet troll.

11. NG - Abbreviation for "Not Good", indicating that something is amiss or unacceptable.

12. ggrks - Short for "guuguru kensaku", meaning "search in Google".

13. JK/JD/JC/JS - Abbreviations denoting high school girls, college girls, middle school girls, and elementary school girls, respectively.

14. 実況プレイ - Gameplay; a recording of a game being played.

15. 演奏してみた - Attempt at playing a musical piece.

16. 歌ってみた - Attempt at singing a song, i.e., a cover.

17. 踊ってみた - Attempt at dancing to a track.

18. Mylist - A favorite list system where users can create folders as bookmarks for favorite content.

19. Nico Nico Pedia - The Nico Nico Douga encyclopedia, where users can add and edit articles on various topics.

20. Nico Nico Seiga - Community of illustrators on the Nico Nico Douga platform where artists can share their work.

21. 弾幕 (danmaku) - Literally "bullet curtain", a term used to describe the large volume of comments that pass across the screen during playback.

22. MAD - Abbreviated term for "Music Anime Douga"; fan-edited videos that combine anime clips with music.

23. UTAU - Free singing synthesis software, popular among Nico Nico users for song creation.

24. VOCALOID - Voice synthesizing technology that allows users to create songs using virtual singers.

25. 投稿 (toukou) - Means "post", referring to uploading a video to the platform.

26. 生放送 (namahousou) - Live broadcasts on Nico Nico Douga.

27. きて (kite) - A word used when a user wants to draw attention to a specific part of a video.

28. 神動画 (kami douga) - Literally "divine video", a term used to describe a very popular or well-made video.

29. 廃人 (haijin) - Literally "wasted person", a jesting term referring to someone addicted to Nico Nico Douga.

30. 黒歴史 (kurorekishi) - Literally "black history", used in the context of embarrassing or failed posts in the past.

31. Nico Nico Medley - A musical remix of various songs combined into one harmonious tune.

32. Nico Nico Chorus - When multiple users sing the same song, and then all versions are merged into one video.

33. アンケート (ankēto) - Poll. Users often conduct polls among viewers on various issues.

34. R-18 - Adult content video, inappropriate for minors.

35. ゲーム実況 (geemu jikkyou) - Video playthroughs with commentary, similar to Let's Plays.

36. 初音ミク (Hatsune Miku) - The most renowned Vocaloid character, frequently appearing on Nico Nico Douga in fan-made videos.

37. Nico Nico Dance - A specific dance style that became popular thanks to the platform.

38. 変更 (henkou) - Change. Users notify about changes in the video or live broadcast.

39. MUGEN - A game-creating engine, popular among creators on Nico Nico Douga.

40. 会場 (kaijou) - Literally "meeting place", a term referring to chat during live broadcasts.

41. Komuro-kei (小室系) - A genre of pop music popular in Japan in the 90s, often found on Nico Nico, named after music producer Tetsuya Komuro.

42. My List (マイリスト) - A feature on Nico Nico that allows users to make their own playlists with favorite videos.

43. Niconico Seiga (ニコニコ静画) - A Nico Nico service for sharing and viewing illustrations.

44. Timeshift - A feature that allows users to watch live broadcasts at a later time.

45. Utattemita (歌ってみた) - Literally "Tried to Sing". A category of videos where users post their renditions of songs.

46. Odoritemita (踊ってみた) - Literally "Tried to Dance". A category where users showcase their dance choreographies to various songs.

47. Niconico Pedia - An online encyclopedia on Nico Nico where users can add and edit information on various topics.

48. Nico Live (Niconico Namahousou) - The section of Nico Nico dedicated to live broadcasts.

49. Zero Ichi Kiseki - A genre of songs that became popular on Nico Nico, characterized by a sudden surge in popularity.

50. Ensoushitemita (演奏してみた) - Literally "Tried to Play". Users post videos where they play on various instruments.

51. Nico Nico Points - Virtual currency used for purchasing various premium features on the platform.

52. MAD Movie - Videos that combine various video clips (often from anime) with music to create new content.

53. Niconico Choukaigi - An annual event organized by Nico Nico where creators and fans can meet and exchange experiences.

54. Nico Ad - The advertising system on Nico Nico Douga that allows creators to earn from their content.

55. YuuNico - A term for collaboration between users of the Nico Nico platform to create content.

56. Dōjin Soft - Independently created games, which often appear and are promoted on Nico Nico.

57. Nico Medley - Remixes and compilations of tracks created by various platform users.

58. Niconico Ryuuseigun - Popular on the platform visualizations of comments flying across the screen during video playback.

59. Danmaku (弾幕) - A term describing the comments feature that flies across the screen on Nico Nico; derived from "bullet hell" games.

60. Tokoton Hanbun - A phenomenon of creating videos that are precisely half of the original, a trend often seen on Nico Nico.

Note: Due to the evolving nature of online platforms, new memes and terminologies may emerge over time. This list aims to provide a snapshot of some of the most common terms up to the time of the last update. For more recent developments, one would need to refer to more current sources.