OBS. 18.—­As to the application of this suffix to nouns, when we consider the signification of the words thus formed, its propriety may well be doubted.  It is true, however, that nouns do sometimes assume something of the nature of verbs, so as to give rise to adjectives that are of a participial character; such, for instance, as sainted, bigoted, conceited, gifted, tufted.  Again, of such as hard-hearted, good-natured, cold-blooded, we have an indefinite number.  And perhaps, upon the same principle, the formation of such words as actionable, companionable, exceptionable, marketable, merchantable, pasturable, treasonable, and so forth, may be justified, if care be taken to use them in a sense analogous to that of the real verbals.  But, surely, the meaning which is commonly attached to the words amicable, changeable, fashionable, favourable, peaceable, reasonable, pleasurable, seasonable, suitable, and some others, would never be guessed from their formation.  Thus, suitable means fitting or suiting, and not able to suit, or capable of being suited.

OBS. 19.—­Though all words that terminate in able, used as a suffix, are properly reckoned derivatives, rather than compounds, and in the former class the separate meaning of the parts united is much less regarded than in the latter; yet, in the use of words of this formation, it would be well to have some respect to the general analogy of their signification as stated above; and not to make derivatives of the same fashion convey meanings so very different as do some of these.  Perhaps it is from some general notion of their impropriety, that several words of this doubtful character have already become obsolete, or are gradually falling into disuse:  as, accustomable, chanceable, concordable, conusable, customable, behoovable, leisurable, medicinable, personable, powerable, razorable, shapable, semblable, vengeable, veritable.  Still, there are several others, yet currently employed, which might better perhaps, for the same reason, give place to more regular terms:  as, amicable, for friendly or kind; charitable, for benevolent or liberal; colourable, for apparent or specious; peaceable, for peaceful or unhostile; pleasurable, for pleasing or delightful; profitable, for gainful or lucrative; sociable, for social or affable; reasonable, for rational or just.

OBS. 20.—­In respect to the orthography of words ending in able or ible, it is sometimes difficult to determine which of these endings ought to be preferred; as whether we ought to write tenable or tenible, reversable or reversible, addable or addible.  In Latin, the termination is bilis, and the preceding vowel is determined by the conjugation