different between votable vs vatable

English

vote +? -able

votable (not comparable)

Capable of being voted upon.
a votable proposal
Eligible to vote.
- 1849, Constitution and By-laws of the Reading Savings Association
  Each member, being a votable citizen of the State shall have the right to vote, but shall have but one ballot.

VAT +? -able.

vatable (not comparable)

On which VAT must be paid.
You will be invoiced for everything — first for the non-vatable items and later for the vatable items.

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