This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 屵 is uncertain. It visually combines 山 (mountain) and 厂 (cliff), but no clear origin is established.
A mountain 山 perched on a cliff 厂 suggests a high, steep place, but the kanji's meaning is not well-defined.
For ガツ, imagine a steep mountain cliff where a sudden gust of wind (ガツ) nearly blows you off. The gust sound cues ガツ while the cliff shape reinforces the scene.