para-
/ˈparə/(also par-)
prefix
1Beside; adjacent to: parataxis parathyroid
1.1Beyond or distinct from, but analogous to: paramilitary paratyphoid
2 Chemistry Denoting substitution at diametrically opposite carbon atoms in a benzene ring, e.g. in 1,4 positions: paradichlorobenzene Compare with meta- and ortho-.
Origin
From Greek para 'beside'; in combinations often meaning 'amiss, irregular' and denoting alteration or modification.