I have been out of the industry for a while , but I am pretty sure it is "Meet And ASsist" .

Not sure if any of the following apply to you , but we used to use "Meet and Assist" requests for older travellers , people with a significant disability , one parent travelling with multiple children etc ... I was never really sure how much notice individual airlines took of the request as feedback from pax was quite mixed . These days with most airlines focussing on keeping their headcount down they do not often have 'spare' staff around to be able to
meet and assist .