The Games section from Macmillan Dictionaries contains interactive games which are intended to improve students' language skills, help them practise and extend vocabulary:
Irregular Verb Wheel Game tests one's knowledge of irregular verb forms.
Irregular Verb Wheel Game tests one's knowledge of irregular verb forms.
Drag and Drop: Sports and American Sports improve one's sporting vocabulary.
Drag and Drop: Pronunciation - "ough" pronunciation game with both the British and the American English version.
Gap-Fill: Pronunciation and Spelling is also available in both the British and the American English version.
Language Study: New Words: one should guess which words are the source of the new ones.