1The refractory nature of the ceramic composite made it ideal for use in high-temperature applications.
2After several rounds of chemotherapy, the cancer proved refractory to further treatment.
3Refractory metals like tungsten and molybdenum are used in the manufacture of high-speed cutting tools.
4The refractory period in a neuron is the time during which it is unable to generate another action potential.
5The team's efforts to rehabilitate the injured athlete were hindered by his refractory attitude towards physical therapy.