Fetching details from the dictionary...

still more; even more; all the more
still less; even less
彼の努力を知ると尚更応援したくなった。
Learning of his efforts made me want to support him all the more.
雨の日は尚更外出したくなくなる。
On rainy days, I want to go out even less.
経験者でも難しいのだから初心者は尚更だ。
If it's hard even for experienced people, it's all the more so for beginners.