not solid

arched cleft cupped curved depressed dimpled excavated indented notched pitted striated sunken vaulted void

alveolate carved out cavernous concave cup-shaped deep-set incurved infundibular troughlike unfilled vacant

convex earnest frank full genuine high honest light meaningful raised real sincere soft solid substantial truthful

defective erroneous false faulty flawed fragile illogical inaccurate incorrect insane insecure shaky unbalanced unhealthy unreliable unsafe unstable

ailing crazed dangerous decrepit delicate demented deranged diseased fallacious frail ill in poor health incongruous infirm insubstantial invalid lunatic mad rickety specious tottering unbacked unhinged unsteady unsubstantial unwell weak wobbly

accurate balanced certain correct firm healthy honest just perfect protected rational reasonable reliable right safe sane secure sound stable steady strong sure true valid well