Cerbera odollam Gaertn.
Recent Synonyms: None relevant.
Status: Native; Vulnerable. Cultivated.
Growth Form or Habit: Tree.
Common Name: Pong Pong
Similar species: Cerbera manghas is similar in appearance but can be distinguish by its flowers, which has a red centre instead of yellow in this species.
More pictures can be found at
(1) Flora Singapura website
(2) The Plant Observatory website