Hyperbole
/haɪˈpɜːr.bə.li/ noun easyExaggerated language not meant to be taken literally, used for emphasis or effect.
When she said she'd told him a million times, that was pure hyperbole, not an actual count.
Memory Trick
'Hyper-' means beyond or over (as in 'hyperactive') — hyperbole pushes a statement way beyond the literal truth purely for dramatic effect.