A drawl is a perceived feature of some varieties of spoken English, and generally indicates longer vowel sounds and/or diphthongs. Varieties of English which are said to feature pronounced drawls include Southern American English, and Broad Australian English.
The Southern Drawl, or the diphthongization or triphthongization of the traditional short front vowels as in the words pat, pet, and pit: these develop a glide up from their original starting position to [j] and, in some cases, back down to schwa.
/æ/ → [æj(ə)]
/ɛ/ → [ɛj(ə)]
/ɪ/ → [ɪj(ə)]