What is the meaning of Flagging?

present participle and gerund of flag

Becoming tired or less dynamic; declining in strength; dwindling.

A pavement or sidewalk of flagstones; flagstones, collectively.

The process by which something flags or tires.

The skewing or bending of the upper part of a television picture due to imperfect synchronization of the video signal.

Use of a handkerchief code or analogous display to signal sexual interests.

Source: wiktionary.org