noun

1. A rope, cable etc. that holds something in place whilst allowing some movement

2. A strong rope or line that connects a sailor's safety harness to the boat's jackstay

3. (by extension) the limit of one's abilities, resources etc.

Synonyms: hobble

verb

1. To restrict something with a tether.

2. To connect a cellular smartphone to another personal computer in order to give it access to a hotspot.