= (v) give out or reflect small flashes of light; when sb's eyes glint, they look bright, expressing a strong emotion
(n) a small flash of light, especially as reflected from a shiny surface
* ebb and flow = (조수처럼) (정도, 수, 양의, 또는 한 상태에서 다른 상태로의 주기적이고 반복적인) 변화, 변동
= something that changes in a regular and repeated way; a frequently changing situation