Rabt ka lughvi maani hai joR ya taalluq. Yeh wo ghair-tehreeri usool hai ke sheʿr ke donon misre mil kar ek hi khayaal ko mukammal karein. Misra-e-oola tamheed qaayam karta hai — ek manzar, ek sawaal, ek mafrooza. Misra-e-saani use khatm karta hai — nateeja nikaalta hai, choT karta hai, jawaab deta hai.
Rabt ke bina sheʿr sirf do hum-qafia satrein hain. Rabt ke saath yeh maani ki ek nanhi machine ban jaata hai. Ghalib ka mashhoor matla leejiye: pehla misra kehta hai hazaaron aarzoo'ein aisi ke har ek par jaan qurbaan; doosra kehta hai bahut si aarzoo'ein poori huin lekin phir bhi kam lageen. Donon mil kar insaan ki khwaahish ke baare mein ek hi, chaunka dene waali baat kehte hain. Koi ek misra tanha yeh baat nahin keh sakta.
Rabt sheʿr ka sab se gehra imtihaan hai. Azeem shoara — Mir, Ghalib, Faiz, Iqbal — aise sheʿr kehte hain jahaan ek misra nikaal dein to doosra bhi TooT jaata hai. Yahi paivastagi asl baat hai.