This is one of the potential files. This specifies the parameters relating to pure elements of Iron and Carbon. It is also possible to have parameters of other pure elements. That way you can have one library.meam file for all alloy potentials and have different files for parameters describing pair interactions between different elements.

# Fe3C (Cementite) library MEAM file used in Phys. Rev. B 89, 094102 (2014)
# Fe potential referenced from J. Phys.: Condens. Matter 24 225404 
# C potential referenced from Phys. Rev. B 81, 104103
# Used together with "FeC.meam" for Fe-C alloy potential parameters 
# elt        lat     z       ielement     atwt
# alpha      b0      b1      b2           b3    alat    esub    asub
# t0         t1              t2           t3            rozero  ibar

'Fe' 'bcc' 8 26 55.847000
5.027000 3.800000 2.000000 0.900000 0.000000 2.851000 4.280000 0.585000
1.000000 -0.800000 12.300000 2.000000 1.000000 0.000000

'C'         'dia'   4.      6            12.0111
4.38        4.26    5.00    3.20         3.980 3.567   7.37    1.490
1.0         7.5             1.04         -1.01         1.0     0