A curved symmetrical structure spanning an opening and typically supporting the weight of a bridge, roof, or wall above it. The ancient stone arch stood firm despite the passage of centuries.
A structure forming a curved top on a doorway, window, or other opening. The grand entrance was marked by a beautifully carved wooden arch.
The rainbow formed a perfect arch across the sky.
The raised curve on the bottom of the foot. She had to wear special shoes to support the arch of her foot.
Playfully roguish or mischievous. She gave him an arch smile, hinting at a secret she wasn't ready to share.
Cunning or sly; having a knowing or superior air. His arch comments often left his colleagues feeling both amused and slightly wary.
Chief; principal; of the highest rank, especially when used attributively before a noun. After years of rivalry, she finally defeated her arch enemy in the championship.