Pansage appears to be a small, green monkey with a yellowish-khaki chin, arms, and chest. It has green legs and tail, which has a pair of small leaves on its tip. The insides of its ears are light green and it has a tree-like appendage atop its head. This "tree" has 3 teardrop-shaped yellowish-khaki marks on it.
Pansage was first seen together with Axew as a toy featured in two images seen in July 2010, but its existence was not yet verified. In the beginning of August a fake leak of the September issue of CoroCoro showed its own version of this Pokémon. Pansage was officially revealed August 22, 2010 by Pokémon Sunday.
Pansage's Japanese name, Yanappu, may come from 柳 yanagi, meaning willow, and ape.
Pansage, with the other elemental monkeys, seem to be based on the Three Wise Monkeys, with Pansage representing "speak no evil" by having its mouth open. Panpour represents "see no evil" by having its eyes closed and Pansear represents "hear no evil" by having a hand to its ear.
If the player chooses Tepig as his/her starter, the player will receive a Pansage from an NPC early in the game. If the player chooses Snivy as his/her starter, the male rival, Cheren, will use a Pansage as part of his team. If the player chooses Oshawott as his/her starter, the player will face Cilan, who uses a Pansage as part of his team, in the first Gym battle and the female rival, Bianca, will also use a Pansage as part of her team.
Its name may be an amalgamation of the words Pan (the genius of Chimpanzees and, in the greek mythology, the God of the Wild) and Sage (a commonly used ingredient in cooking and a herb).