## In amino acid|lang=mul terms the difference between r and m

is that

**r** is iupac 1-letter abbreviation for arginine while

**m** is iupac 1-letter abbreviation for methionine.

## As letters the difference between **r** and **m**

is that

**r** is the eighteenth letter of the while

**m** is the thirteenth letter of the.

## As symbols the difference between **r** and **m**

is that

**r** is roentgen (

*unit *) while

**m** is mega- or

**m** can be the roman numeral

**m ** (1,000).