ETYM Cf. French stoďcisme.
Belief in indifference to pleasure or pain.
An indifference to pleasure or pain; SYN. stolidity, stolidness.

The philosophy of the Stoics
The philosophical system of the Stoics following the teachings of the ancient Greek philosopher Zeno.
Greek school of philosophy, founded about 300 bc by Zeno of Citium. The stoics were pantheistic materialists who believed that happiness lay in accepting the law of the universe. They emphasized human brotherhood, denounced slavery, and were internationalist. The name is derived from the porch on which Zeno taught.
In the 3rd and 2nd centuries bc, stoics took a prominent part in Greek and Roman revolutionary movements. After the 1st century bc stoicism became the philosophy of the Roman ruling class and lost its revolutionary significance; outstanding stoics of this period were Seneca, Epictetus, and Marcus Aurelius Antoninus.