Conscripted military service is a thing of the past (there's always some talk to bring it back) so military slang is less relevant, younger generations hear expressions which were born in the military and were implanted and inherited during service, less and less, probably not at all. But back then when a large proportion of the society spent some mandatory time in the military these idioms sipped into civilian life too. Maybe I'll list more in the future, right now only have time for a couple.
centit vágni or vágom a centit = "cutting the centimeter", "I'm cutting the centimeter"; waiting for the end of something, in the military typically the end of service. This isn't a figure of speech, they bought tailor's measuring tape (back than it was paper based I think, now I could only find images of plastic) and every day passed they cut one centimeter of it, then on the last day they used as confetti.
kopasz = "bald/baldie"; fresh conscript, those in still basic training, maybe longer, depending on the length of service. The lowest in the ranks.
fóka, fókázni = "seal" (the animal), "doing the seal"; mop and mopping. This served as both cleaning purposes and bullying the baldies. Longer serving soldiers spilled soap foam all over the barracks by the buckets and on the basis of seniority demanded the baldies to clean it up. The cleaning went with a piece of flat wood wrapped in a rag, this was called "seal", and the crawling around on four and cleaning is the "doing the seal".
motoros fóka = "motorized seal". Senior conscript were done with doing the seal they could use more advanced tools, flat peace of wood with long wooden handle (they could use proper mop basically), so they didn't have to crawl on four.