The singular noun is proof.
The word proof is also a verb and an adjective.
jewish priests
analysis itself is a singular form
The noun form 'cut' is singular; the plural form is 'cuts'.
The noun genius is the singular form, the plural form is geniuses.
The singular possessive form of criterion is criterion's
The possessive form of the plural noun proofs is proofs'.Example: I'm waiting for the proofs' delivery from the printer.
Evidence does not have a plural form, as it is an uncountable noun. It is like information, or furniture, or even news, which, in spite of the final -s is always singular. So, you can have "a piece of evidence", or "pieces of evidence", but not "evidences".
It is singular: an other, pronounced a-nother. This word is one of the proofs that normal English speech is run together.
The singular form of the demonstrative pronoun 'these' is this.
The singular form of feet is foot.
The singular form of "hypothysis" is "hypothesis."
jewish priests
The singular form is ombudsman.
it is already in its singular form.
The singular form is money.
The singular form is cuff.
The singular form is hilum.