深まる

deepen, grow deeper

深 deep + まる become more
verb · present tense Rare #43,893
deepen, grow deeper Often used for abstract things, such as mysteries, feelings, or relationships.
JA: 話し合うほど、二人の理解が深まる。
EN: The more they talk, the deeper their understanding grows.

謎は深まる一方だわ。

The mystery only deepens.

謎は深まるばかり。

The mystery only deepens.