concave
adjective
[ ˈkɒnkeɪv ]
• having an outline or surface that curves inwards like the interior of a circle or sphere.
• "concave lenses"
Similar:
curved inwards,
hollow,
hollowed out,
scooped out,
depressed,
sunken,
indented,
recessed,
incurved,
incurvate,
Origin:
late Middle English: from Latin concavus, from con- ‘together’ + cavus ‘hollow’.
