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through thick and thin
/θruː ˈθɪk ənd ˈθɪn/◆idiom
loyal support
She stood by him through thick and thin.
She supported him in both good and bad times.
informal
to remain loyal and supportive regardless of circumstances
Their friendship survived through thick and thin.
Their friendship stayed strong despite all hardships.
He promised to love her through thick and thin.
He vowed to love her in both happy and difficult moments.
Usually follows verbs such as stand, stay, remain, or love.
Collocations
stand by someone through thick and thinremain loyal to someone in all situationsstay together through thick and thinremain together despite challenges
English Dictionary