Synonyms for high turnover include: ^{powerthesaurus.org 1 2 3}

• Excessive turnover
• Expensive turnover
• High staff turnover
• High attrition
• High level of turnover
• High rate of staff turnover
• High rate of turnover

Other synonyms for turnover include upset, turnover rate, overturn, dollar volume, and employee turnover. ^{synonyms.com 4}