Snail

n. gastropod mollusk with a coiled shell; slow person, sluggard

The word snail is loosely applied to almost all members of the molluscan class Gastropoda which have coiled shells in the adult stage. The class Gastropoda is the second largest class of invertebrates, second only to the insects. Because of this, snails are extraordinarily diverse, in habitat, in form, in behaviour and in anatomy, and therefore what is true of one snail species may not at all be true of another, more distantly related one. In other words it is extremely hard to generalize accurately about "snails" in the wider sense of the word.
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Noun
1. freshwater or marine or terrestrial gastropod mollusk usually having an external enclosing spiral shell
(hypernym) gastropod, univalve
(hyponym) scorpion shell
2. edible terrestrial snail usually served in the shell with a sauce of melted butter and garlic
(synonym) escargot
(hypernym) meat
(substance-holonym) edible snail, Helix pomatia
Verb
1. gather snails; "We went snailing in the summer"
(hypernym) gather, garner, collect, pull together
(hyponym) whelk
(derivation) escargot

(n.)
The pod of the sanil clover.
  

(n.)
Hence, a drone; a slow-moving person or thing.
  

(n.)
Any one of numerous species of terrestrial air-breathing gastropods belonging to the genus Helix and many allied genera of the family Helicidae. They are abundant in nearly all parts of the world except the arctic regions, and feed almost entirely on vegetation; a land snail.
  

(n.)
Any gastropod having a general resemblance to the true snails, including fresh-water and marine species. See Pond snail, under Pond, and Sea snail.
  

(n.)
A tortoise; in ancient warfare, a movable roof or shed to protect besiegers; a testudo.
  

(n.)
A spiral cam, or a flat piece of metal of spirally curved outline, used for giving motion to, or changing the position of, another part, as the hammer tail of a striking clock.
  

Snails crawling in your dream, signifies that unhealthful conditions surround you.

To step on them, denotes that you will come in contact with disagreeable people.