Tablet obscuring last third of column (4)

I believe the answer is:

pill

I'm a little stuck... Click here to teach me more about this clue!

'tablet' is the definition.
(I know this)

I cannot understand how the rest of the clue works.

(Other definitions for pill that I've seen before include "Pellet of medicine" , "Medical tablet" , "Medicinal pellet" , "nuisance to put up with" , "Medicinal tablet" .)

I've seen this clue in The Daily Mail.

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