IPA: /ˈdɪʃˌwɔːtə/
KK: /ˈdɪʃˌwɔːtər/
Water that is used for washing dishes, often dirty and soapy.
After dinner, she filled the sink with dishwater to clean the plates.
The word 'dishwater' is formed from 'dish' (from Old English *disc*, meaning a plate or vessel) and 'water' (from Old English *wæter*, meaning water). The term 'dishwater' refers to the water used for washing dishes.
Think of a 'plate' ('dish') being washed in 'water' — that's what dishwater is, the water used for cleaning dishes.