What's the meaning of the expression "Grab a hold"?

What does it mean to "grab a hold"? There is a song by Cyndi Lauper that says

If you wanna grab a hold, let it go...

The phrase is actually "grab ahold", and when you grab ahold of something, you grasp it or hold onto it.

For example, if you are watching a scary movie with someone, you might grab ahold of their arm during the frightening parts.

• grab a hold of yourself: don't lose heart, control yourself

Grab a hold of yourself, grab a hold of your mind and change your life.

ldoce defines:

• Catch/grab/seize etc hold of something = start holding something quickly and firmly

She grabbed hold of letter and tore it open.

• grab a hold of [sb's arm]: take hold of someone or something with a sudden or violent movement

Kay grabbed hold of my arm to stop herself falling.

Note: The term get a hold of somebody/something has a different meaning.