Word-formation in the Oxford Latin Dictionary

The OLD often leaves the impression that Latin words were formed by taking one free-standing word and adding a suffix or another free-standing word.

Examples include:

naufragō ... [as next + -O^3]

naufragus^1 ... [= NAVIFRAGUS]
naufragus^2 ... [prec.]
...
nāuiculārius ... [NAUICLA + -ARIUS]

nāuifragus 'shipwrecking' is an exception: [NAVIS + frag- (FRANGO) + -VS]. Here, at least (other instances have yet to be found), we are told that it is the root frag-, as seen in frango, that is involved.