This is a glossary of some of the most commonly used terms in anime.
Anime: a Japanese word for animation; it is used by Western fans to refer to animation produced in Japan
Baka: a term that is heard often in anime as an insult. It can be used to mean "stupid," "fool," or "idiot"
BGM: Background music
Bishojo: beautiful girl
Bishonen: beautiful boy
Catgirl: a female cat-human hybrid character; this is generally a cute girl with catlike ears and sometimes a tail
Chibi: a commonly used alternate term for super deformed; however, this technically is not correct. "Chibi" is a Japanese word meaning "small child" or "dwarf"
Con: short for convention, and usually applies to anime conventions
Cosplay: this is short for "Costume Play"; a practice of dressing up as one’s favorite anime character
Ecchi or Etchi: humorously indecent, and usually involves gratuitous nudity or sexual innuendo; ecchi/etchi is milder than hentai
Eyecatch: the visual in anime that comes before and after an advertising break; it visually summarizes the show's nature and features the main characters
Face fault: an exaggeration of facial features to convey extreme shock or surprise
Fan service: this usually refers to unnecessary things thrown into a story to capture the interest of adolescent male fans; it can also refer to anything unrelated to a story but included to please fans (such as fancy outfits and cute animals)
Fansub: a fan-subtitled production, the term is usually used for those properties where these are the only translations of less popular anime titles
Hammerspace: when an angry woman summons a mallet from nowhere and strikes someone with it
Henshin: a transformation scene, most often seen in Magical Girl anime
Hentai: Japanese word meaning "perverted"
Josei: anime that is targeted at young women
Kawaii: a Japanese word meaning "cute," it also refers to character designs
Kodomo: anime that is targeted at all children, regardless of gender
Magical Girl: this term refers to a specific genre featuring young girls with some sort of magical power
Mahou Shoujo: Japanese for "Magical Girl"
Manga: is usually used to mean Japanese comic books
Mecha: short for mechanical, and refers to technology ranging from guns to vehicles to giant robots
Mobile Suit: powered armor, and is a human-piloted robotic flying machine; this is a subset of mecha
OAV / OVA: short for Original Animation Video / Original Video Animation; this refers to anime made specifically for direct-to-video release
OST: Original soundtrack
Otaku: in anime, it refers to someone obsessed with a particular hobby
Sakura: Japanese word for "cherry blossoms." In anime, cherry blossoms are a symbol of death.
Seinen: anime that is targeted at teenage boys and young adult males
Seiyuu: a Japanese term for voice actor or actress
Sensei: a term often heard in anime when a student is addressing a teacher, or when an underclassman is addressing an upperclassman at school
Settei: the preparatory line work used by animators as a design reference at the beginning of an anime project
Shojo: anime that is targeted at young girls
Shonen: anime that is targeted at young boys
Super deformed: a style of anime where characters are drawn in an exaggerated fashion
Sweat drop: a visual stylization used in anime; when a character feels embarrassed, perplexed, or self-conscious, a large tear-shaped drop will appear near their face or head