Super deformed or SD is a specific style of Japanese caricature where characters are drawn in an exaggerated way, typically small and chubby, with stubby limbs and oversized heads, to make them resemble small children.
The style is closely related to the chibi concept.
It is often also used on anime and manga in brief interjections to show an extreme or exaggerated emotion, such as anger or surprise, that would be difficult to portray or would seem out of character if expressed on a more realistic face. They are meant to be cute and are often used in humorous diversions from the storyline.
Recent trends in anime have shifted away from super-deformed character designs, yet the traditional anime character designs remain.
Proportions are often measured using head length as a guide. The average adult is considered to stand seven (1:7) to seven and a half heads tall. Idealized figures are often drawn eight heads(1:8) in length.
The head of a super deformed character is normally anywhere between one third (1:3 ratio) and one half (1:2 ratio) the character's height, often a golden ratio (38 percent), with the eyes taking up much of the space on the head. Some artists may use alternative proportions. There are other exaggerated proportions (such as the 1/5th proportion, as used by Tales of Eternia, etc) that are popular in anime, but are not considered SD.
- Chibi Land Sailor Moon site devoted to Chibis and Super deformed
- Super deformed defined at Anime News Network.