1. noun /ɑːtʃ,ɑɹtʃ/
a) An inverted U shape.
b) An arch-shaped arrangement of trapezoidal stones, designed to redistribute downward force outward.
2. verb /ɑːtʃ,ɑɹtʃ/
To form into an arch shape
The cat arched its back
3. adjective /ɑːtʃ,ɑɹtʃ/
I attempted to hide my emotions, but an arch remark escaped my lips.
b) Principal; primary.
The man is my arch rival, without him I would have no competition.
See Also: arc
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