恬 is literary and rarely stands alone in modern Chinese. You will see it almost exclusively in compounds:
恬静 (tiánjìng, quiet/peaceful),
恬淡 (tiándàn, indifferent to fame),
恬不知耻 (tián bù zhī chǐ, brazen — literally calmly unaware of shame). Note the
心 (heart) radical — the calm is internal.
