Mid 17th century (in an earlier sense). From classical Latin retūsus not sharp, blunt, in post-classical Latin and scientific Latin also having a broad or rounded end with a notch or indentation at the apex, use as adjective of past participle of retundereretund.
Definition of retuse in US English:
retuse
adjective
Botany. Of a leaf, petal, etc.
Origin
Mid 17th century (in an earlier sense). From classical Latin retūsus not sharp, blunt, in post-classical Latin and scientific Latin also having a broad or rounded end with a notch or indentation at the apex, use as adjective of past participle of retundere retund.