Crikey/ˈkraɪki/ Definition 1 of 3Pro Tip 1/3Expressing Amazement Use 'crikey' to show you are amazed by something unexpected or unusual. Crikey, that magic trick was unbelievable! Pro Tip 2/3Informal Situations Best suited for casual conversations with friends or in relaxed environments. Crikey, you've changed your hairstyle since I last saw you! Pro Tip 3/3Avoid in Formality Not appropriate in formal writing or speech; use more formal expressions there. Crikey, what an unexpected honor!