Undoubtedly means there is nothing left to argue about. 'She is undoubtedly the best cook in the family' — nobody at the table is going to put a hand up.
It works as a whole-sentence adverb, sitting at the front with a comma, or right in front of the word it strengthens: undoubtedly true, undoubtedly the strongest candidate. Careful writers use it to give ground before a but: 'Undoubtedly he worked hard, but the plan was wrong from the start.' In speech, definitely and certainly do the same job with less ceremony. Watch the spelling: the silent b of doubt survives, and it is undoubtedly, never undoubtably. The adjective underneath is undoubted — an undoubted success, an undoubted talent.
1adverbundoubtedlyWithout any doubt at all.
“The film is undoubtedly her finest work.”
synonyms: certainly, unquestionably
2adverbadmitUsed to admit a point before disagreeing with it.
“Undoubtedly the price is high, though the machine will last twenty years.”
Also accepted in games: certainly, definitely
Undoubtedly is homemade. Middle English wrote undoutedly, which is undoubted with -ly stuck on the end, and that spelling shows the b was not there at first. The letter arrived later, and it has stayed silent ever since.
Middle English
undoutedly
English, today
undoubtedly
From Middle English undoutedly, equivalent to undoubted + -ly.
Etymology from Wiktionary, CC BY-SA
Practised in Sharper Adjectives, A Man Called Ove
First appears in chapter 14 of A Man Called Ove.
Practise this word