Belabor, v. t. [imp. & p. p. Belabored; p. pr. & vb. n. Belaboring.]
1. To ply diligently; to work carefully upon. "If the earth is belabored with culture, it yieldeth corn." Barrow.
2. To beat soundly; to cudgel. Ajax belabors there a harmless ox. Dryden.
Shades of meaning
Fernald has no entry of its own for belabor; he lists it under beat.
Where he writes about it:
Others of the above words describe the manner of beating, as bastinado, to beat on the soles of the feet; belabor, to inflict a comprehensive and exhaustive beating; cudgel, to beat with a stick; thrash, as wheat was beaten out with the old hand-flail; to pound (akin to L. pondus, a weight) is to beat with a heavy, and pommel with a blunt, instrument. — from beat