1. not stopping or becoming less intense; continuing without pause or relief
2. showing no mercy or compassion; harsh and inflexible

Examples

• The unrelenting rain flooded the streets for three days straight.
• She faced unrelenting criticism from her opponents during the campaign.
• The coach’s unrelenting training schedule pushed the athletes to their limits.
• Despite unrelenting pressure from investors, the CEO refused to cut jobs.
• The desert sun beat down with unrelenting heat.
• His unrelenting pursuit of perfection made him difficult to work with.
• The unrelenting pace of modern life leaves little time for relaxation.