What is the meaning of track clothes?

Tracksuit. A tracksuit is an article of clothing consisting of two parts: trousers and a jacket usually with front zipper. It was originally intended for use in sports, mainly as what athletes wore over competition clothing and would take off before competition.

What does FIRK mean?

intransitive verb. 1 dialectal, British : to move quickly : hasten also : to be lively or frisky. 2 dialectal, British. a : jerk, twitch.