up and down

Significat

Adv

1. upward and downward, alternately.
2. alternately forwards and backwards along a path
3. staunchly, unwaveringly, obstinately
4. In various places, e.g. in a country.

Adj

1. Vertical; perpendicular; said of the cable when the anchor is under, or nearly under, the hawse hole, and the cable is taut.
2. plain; downright

Sents

When she saw the unknown object bobbing up and down the edge , she was absolutely horrified .