The difference between Cipher and Oh

When used as nouns, cipher means a numeric character, whereas oh means an utterance of oh.

When used as verbs, cipher means to calculate, whereas oh means to utter the interjection oh.

check bellow for the other definitions of Cipher and Oh

Cipher as a noun:

A numeric character.
Cipher as a noun:

Any text character.
Cipher as a noun:

A combination or interweaving of letters, as the initials of a name; a device; a monogram.

Examples:

"a painter's cipher, an engraver's cipher, etc."
Cipher as a noun:

A method of transforming a text in order to conceal its meaning.

Examples:

"The message was written in a simple cipher. Anyone could figure it out."
Cipher as a noun (cryptography):

A cryptographic system using an algorithm that converts letters or sequences of bits into ciphertext.
Cipher as a noun:

Ciphertext; a message concealed via a cipher.

Examples:

"The message is clearly a cipher, but I can't figure it out."
Cipher as a noun:

A grouping of three digits in a number, especially when delimited by commas or periods:

Examples:

"The probability is 1 in 1,000,000,000,000,000 — a number having five ciphers of zeros."
Cipher as a noun (music):

A fault in an organ valve which causes a pipe to sound continuously without the key having been pressed.
Cipher as a noun:

A hip-hop jam session.
Cipher as a noun:

The path (usually circular) shared cannabis takes through a group, an occasion of cannabis smoking.
Cipher as a noun:

Someone or something of no importance.
Cipher as a noun (dated):

Zero.

Cipher as a verb (intransitive, regional, dated):

To calculate.

Examples:

"I never learned much more than how to read and cipher."
Cipher as a verb (intransitive):

To write in code or cipher.
Cipher as a verb (intransitive, music):

Of an organ pipe: to sound independent of the organ.
Cipher as a verb (obsolete):

To decipher.

Examples:

"rfquotek Shakespeare"

Oh as a noun:

An utterance of oh; a spoken expression of surprise, acknowledgement, etc.

Oh as a verb (intransitive):

To utter the interjection oh; to express surprise, etc.