The Allen and Greenough is still under construction;
so some links may not work quite the way you would expect.
252. Adjectives expressing passive qualities,
but occasionally active, are formed by means of the suffixes -
| -ilis, -bilis, -ius,
-tilis (-silis)|| frag-ilis, frail; |
| nó-bilis, well known, famous;
|| nóscere (GNO), to
choice, rare (cf. é-greg-ius); || eximere, to take out, select. |
ag-ilis, active; ||
agere, to drive. |
hab-ilis, handy; ||
habére, to hold.
| al-tilis, fattened
(see note); || alere, to
NOTE: Of these, -ius is
primary, but is also used as secondary (cf. § 241. b. N.).
-ilis is both primary (as in agilis, fragilis) and secondary (as in similis, like, cf. oo , oo , English same); -bilis is in some way related to -bulum and -brum (§ 240. N.); in -tilis and -silis,
-lis is added to to-
(so-), stem of the perfect participle:
as, fossilis, dug up (from fossus, dug); volátilis, winged (from volátus, flight).