BELABOUR
belabor, belabour
(verb) attack verbally with harsh criticism; “She was belabored by her fellow students”
belabour, belabor
(verb) beat soundly
belabor, belabour
(verb) to work at or to absurd length; “belabor the obvious”
Source: WordNet® 3.1
Etymology
Verb
belabour (third-person singular simple present belabours, present participle belabouring, simple past and past participle belaboured)
(transitive) To labour about; labour over; work hard upon; ply diligently.
(British spelling, transitive) To beat soundly; thump; beat someone.
(British spelling, transitive) To attack someone verbally.
(British spelling, transitive) To discuss something repeatedly; to harp on.
Source: Wiktionary