Adjective
flexy (comparative flexier or more flexy, superlative flexiest or most flexy)
Implying or indicating an ability, capacity, or tendency to flex; flexible; bendy.
"Flexy in the upper back and soft enough that you can feel the two headrest rods." Source: Internet
I have one of these as well, and I am running into problems when I switch from ABS to FLEXY or PLA plastic strands. Source: Internet