"belief in the principle of abolishing (something)," 1790, in a purely anti-slavery sense (distinguished from opposition to the slave trade); from abolition + -ism.
Entries linking to abolitionism
abolition n.
1520s, "act of abolishing; state of being abolished," from French abolition or directly from Latin abolitionem (nominative abolitio) "an abolition, an annulling," noun of action from past-participle stem of abolere "destroy" (see abolish). Related: Abolitionary ("destructive"); abolitional ("pertaining to abolition").
Specific application to "opposition to the trans-Atlantic African slave trade" as a political question is first attested 1788. By 1823 abolition was being used in regard to proposals or arguments to end American slavery itself, and after 1832 this was the usual sense of the word until the effort was accomplished by the 13th Amendment (1865). The alternative noun abolishment (1540s) seems not to have acquired a special use in reference to slavery issues.
-ism
word-forming element making nouns implying a practice, system, doctrine, etc., from French -isme or directly from Latin -isma, -ismus (source also of Italian, Spanish -ismo, Dutch, German -ismus), from Greek -ismos, noun ending signifying the practice or teaching of a thing, from the stem of verbs in -izein, a verb-forming element denoting the doing of the noun or adjective to which it is attached. For distinction of use, see -ity. The related Greek suffix -isma(t)- affects some forms.