Crossword Genius

Solemn undertaking to abstain from drinking a toast (6)

Ross

I believe the answer is:

pledge

This clue is a double definition.

'solemn undertaking to abstain' is the first definition.

'drinking a toast' is the second definition.

'from' is the link.

(Other definitions for pledge that I've seen before include "Promise, word of honour" , "Promise solemnly and formally" , "Solemn undertaking" , "Promise or pawn" , "Plight" .)

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