IPA: /ˈdʌkər/
KK: /ˈdʌkər/
A person or thing that ducks or bends down quickly, often to avoid something.
The ducker quickly avoided the flying ball by bending down.
The word 'ducker' is derived from 'duck' (from Old English 'duce', meaning to lower the head or body quickly) and the suffix '-er' (meaning a person who). A 'ducker' is a person who ducks or lowers themselves quickly, often to avoid something.
Think of someone quickly 'lowering' their head or body — that's what a 'ducker' does.