• 圧力あつりょく — pressure, coercion
• 血圧けつあつ — blood pressure
• 気圧きあつ — atmospheric pressure
• 圧倒あっとう — overwhelming (force or numbers)
• 低圧ていあつ — low pressure

圧 is a 略字 (simplified form) of the older character 壓あつ. The structure includes the radical 土 (earth) and a compressed or pressing shape above, visually suggesting pressure or something being pushed down.

血圧けつあつが 高たかすぎます。
Your blood pressure is too high.

圧力あつりょくを 感じかんました。
I felt pressured.

The reading アツ is used in compound words, especially technical or formal terms like 気圧 and 圧力. There are no common kun-yomi for 圧.