What is another word for on one head?
Pronunciation: [ˌɒn wˈɒn hˈɛd] (IPA) 
The phrase "on one head" is an idiomatic expression used to indicate that a responsibility or blame rests solely on one individual. Synonyms for "on one head" include "solely responsible," "accountable," "culpable," "to blame," "answerable," and "guilty." Other options include "bearing the brunt," "carrying the weight," "taking the heat," "being in the hot seat," and "shouldering the burden." These phrases all convey the idea that the responsibility for a particular situation lies squarely on one person's shoulders. Using alternative phrases can enrich your writing by varying your language and avoiding repetition, making your writing more engaging and effective.
