chill
to send a chill down somebody's spine

curvature
curvature of the spine

Papuan Spine-tailed Swift
Mearnsia novaeguineae

Philippine Spine-tailed Swift
Mearnsia picina

run down
a cold shiver ran down her spine

send
it sent a shiver down my spine

spine
espinhaço

spine-chilling
que provoca calafrios