belabor

verb (used with object)

1. to explain, worry about, or work at (something) repeatedly or more than is necessary: He kept belaboring the point long after we had agreed.
2. to assail persistently, as with scorn or ridicule: a book that belabors the provincialism of his contemporaries.
3. to beat vigorously; ply with heavy blows.
4. Obsolete. to labor at.

v.

1590s, “to exert one’s strength upon,” from be- + labor (v.). But figurative sense of “assail with words” is attested somewhat earlier (1590s); and belabored is attested from mid-15c. with a sense of “tilled, cultivated.”