ETYM Old Eng. herken. Related to Hearken.
To listen; used mostly in the imperative; SYN. harken, hearken.
To pay close attention; to listen.

1. Hearken.
2. Hark back — usually used with back.

1. To listen
2. To give respectful attention

1. To hear with intention
2. To listen and pay attention; SYN. hear, take heed.