adverb
BAD : I utterly hope you won't be angry with me.
GOOD : I sincerely hope you won't be angry with me.
BAD : I have to make sure that our customers are utterly satisfied.
GOOD : I have to make sure that our customers are completely satisfied.
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Utterly is usually used with words that have a negative meaning or express strong disapproval such as (adjectives) ridiculous, absurd, irrelevant, useless, wrong, impossible, (adjectival participles) confused, amazed, dejected, ruined, (verbs) reject, detest, destroy : 'This new tin opener is utterly useless.' 'The whole idea is utterly absurd.' 'I'm utterly amazed.' 'The entire building was utterly destroyed.'