adverb
more and more; increasingly; all the more
Literary adverb expressing a gradual intensification, similar to ますます or いよいよ but with a classical, often emotive tone. Used in written or formal speech.
See also: 益々 (ますます) · 愈 (いよいよ)
秋が深まるにつれて、うたた寂しさが募る。
As autumn deepens, I feel increasingly lonely.
彼の言葉に、うたた不安を覚えた。
His words made me feel all the more uneasy.
The origin is uncertain; it may be related to classical Japanese adverbial forms. The kanji 転 ('revolve, change') is likely an ateji used for its sound or associated nuance of shifting states.