From Longman Dictionary of Contemporary Englishtailspintail‧spin /ˈteɪlˌspɪn/ noun [countable usually singular]  1  → in/into a tailspin2 TTAwhen a plane falls through the air, with the front pointing downwards and the back spinning in a circle
                                                    
                                                Examples from the Corpus
tailspin• But I don't go into a tailspin over it.• Lenny's career went into a tailspin when he decided personality mattered more than material.• The economy went into a tailspin.• Its shares went into a tailspin. 
