Google keyboard. Long press return/enter key. Options prev?

[irfanintekhab]

When I long press the return/enter key. I see two options. One is the emoji keyboard. And other says prev. I can't seem to be able to figure out what this prev means. Does anyone know?
Curiosity is killing me! Haha

 

[B. Diddy]

It means previous, as in previous field. If you're at the beginning of a bunch of fields, it will say Next.