diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index add6b03..6c09b3a 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -516,7 +516,7 @@
  *                 mbedtls_x509_crt_init().
  * \param buf      The address of the readable buffer holding the DER encoded
  *                 certificate to use. On success, this buffer must be
- *                 retained and not be changed for the liftetime of the
+ *                 retained and not be changed for the lifetime of the
  *                 CRT chain \p chain, that is, until \p chain is destroyed
  *                 through a call to mbedtls_x509_crt_free().
  * \param buflen   The size in Bytes of \p buf.