from French -iques, Latin -ica, or Greek -ika, plural forms.
A noun ending in -ics meaning ‘a subject of study or branch of knowledge’ will usually take a singular rather than a plural verb, e.g. politics is a blood sport; classics is hardly studied at all these days. However, the same word may take a plural verb in cases where the sense is plural: many of the classics were formerly regarded with disdain.
Definition of -ics in:
- The US English dictionary