Yes, it is possible, but your cell will become text and therefore can't be summed (e.g.) later with another one without removing the m2)
If in Cell(1,2) you want to have the result of Cell (1,1) + m2, write the code as follows:
=C1 & " m2"
The '&' concatenate one string with another. Your first string is determined by the result of C1 and second is enabled by the ' " ' text operator.
good luck