IPA: /ˈriːpər/
KK: /ˈriːpər/
A person or machine that cuts and gathers crops, especially grain, during harvest time.
The farmer used a reaper to collect the wheat from the field.
Reaper → It is formed from "reap" (from Old English *reopan*, meaning to cut or harvest) and "-er" (meaning a person who). A reaper is a person who cuts or harvests crops.
Think of someone who 'cuts' ('reap') crops — the '-er' just means a person. A reaper is someone who harvests.