about to vs on the verge of

[micaelo]

Is there a difference between these two words? Thank you

[oregeezer]

Small degree of difference.
"about to" is a general term used in many senses.
"on the verge of" is most used in referring to feelings or emotions. It is generally meant as closer to happening than "about to".
About to collapse = I feel like I might.
On the verge of collapse = Don't think I can prevent it.