What does the word 'burst' mean in QOS part?

[rick.shin]

In the following page, http://www.cisco.com/en/US/products/sw/iosswrel/ps1828/products_configuration_guide_chapter09186a00800ca59f.html

there is a definition of 'burst size' like this.

[Burst size—Also called the Committed Burst (Bc) size, it specifies in bits per burst how much can be sent within a given unit of time to not create scheduling concerns.]

In the above definition, what does the word 'burst' mean?

I'm not English speaking man,

so when I read the word 'burst', I only think the meaning of 'explosion'..

I want to understand more exactly the meaning of 'burst'.

Thanks in advance...

[hlow]

In that context, you could think the burst size as in how much extra you can send.