punctiform: Dimensions too slight for defining form by naked eye; minute, raised, hemispherical.
Pores very small and numerous, punctiform, disposed into very numerous parallel transverse rows.
The central region contains in its interior the commissural portion, forming a punctiform, rounded mass in each ganglion.
punctiform punc·ti·form (pŭngk'tə-fôrm')
Very small but not microscopic.