Heard - saw - that woman get a creepy-crawly (6)
I believe the answer is:
spider
'a creepy-crawly' is the definition.
(spider is a kind of invertebrate)
'heard saw that woman' is the wordplay.
I cannot really see how this works, but
'woman' could be 'de' and 'de' is found in the answer.
This explanation may well be incorrect...
'get' acts as a link.
Can you help me to learn more?
(Other definitions for spider that I've seen before include "Small creature" , "Miss Muffet frightener?" , "Eight-legged creatures" , "One has eight legs" , "Creepy-crawly" .)