Interesting result for f3r with an ngram Genetic Algorithm

[R. Sale]

So, here's my method - fast and dirty. I took a Latin dictionary, and made a note where I happened to see a whole column of words starting with the same four letters.

Results: circ, coll, comm, comp, conc, conf, cong, cons, cont, conv, disp, diss, ibus, inve, perp, pers, pert, prae, proc, prop, pros, quad, quat, quin, semi

A few with five letters: inter, super, trans

Some additional, more common, three letter possibilities: acc, des, dis, exc, exp, exs, ill, inc, ins, per, pro, rec, rep, res, sub, tri