to pass into another form or kind by a series of intermediate grades
an intermediate grade; transitional form
intransitive verbin·ter·grad·ed, in·ter·grad·ing, in·ter·grades
To merge into each other in a series of stages, forms, or types.
A transitional stage, form, or type.
(third-person singular simple present intergrades, present participle intergrading, simple past and past participle intergraded)