close; intimate · to strengthen (ties, cooperation etc) · closely; intently; carefully · (math.) to osculate

We observed this plant closely for a few weeks.

A tsunami is coming, so please be on the alert.

She was closely related to the mighty Queen Zurline, and her home was beneath the shade of a widespreading oak.

Dutch is closely related to German.

The amount of paper produced by a country is closely related to its cultural standards.