noun, noun or participle which takes 'suru', intransitive verb
studying for a test; cramming for an exam
Casual, abbreviated slang used mainly among students. The full form is テスト勉強.
See also: テスト勉強
明日の試験のためにテス勉しなきゃ。
I have to cram for tomorrow's exam.
I'm just studying for tests all the time and have no time to play.