sway in wind
颭 centers on gentle, wind-driven movement: something swaying or fluttering in a breeze.
颭 combines 風 (wind) with 占, which likely contributes the sound. The character expresses the idea of something moving or swaying in the wind.
The wind enclosure 風 wraps around 占, like a breeze gently swaying a fortune-teller's banner. Picture the banner fluttering softly in the wind.
For セン, imagine a thousand (千, せん) blades of grass all swaying together in the wind: 千 -> セン, and the whole field moves as one.