Squoval

Squoval is a portmanteau of the terms and shapes "square" and "oval." The word can refer to the not quite oval, not quite square shape of a fingernail or toenail.  "Essentially a conservative square with the length of a square nail but the softer edges of an oval" the term was coined to refer to fingernail shape in 1984 by Paula Gilmore, a prominent stylist and educator, according to Peters.  This style was popular in the 1990s, and is still a popular natural nail shape. This article is licensed under the GNU Free Documentation License. 

Source: http://en.wikipedia.org/wiki/Squoval