As nouns the difference between sucking and haustellum
is that sucking is an act of sucking while haustellum is a sucking organ, in the form of a proboscis, in many insects and crustaceans.
As a verb sucking
is .
sucking
English
Verb
(head)
Noun
(
en noun)
An act of sucking.
A sound or motion that sucks.
haustellum
English
Noun
(haustella)
A sucking organ, in the form of a proboscis, in many insects and crustaceans