noun, noun which may take the genitive case particle 'no'
one's only trick; the one thing one knows; a one-track mind
Often used critically to describe someone who keeps repeating the same idea, phrase, or method because it is all they know. Common in the phrase 一つ覚えのように.
彼は一つ覚えのように同じ話を繰り返す。
He repeats the same story like a broken record.
あの政治家の
That politician's speeches are all about tax cuts—it's his one and only message.