the earlier form of poulterer (q.v.). Poetic poulter's measure (1570s), a combination of lines of 12 and 14 syllables, is said to be so called for suggesting "the poulter's old practice of giving an extra egg with the second dozen." [Miller Williams, "Patterns of Poetry," 1986].
The commonest sort of verse which we vse now adayes (viz. the long verse of twelue and fourtene sillables) I know not certainly howe to name it, vnlesse I should say that it doth consist of Poulter's measure, which giueth xii. for one dozen and xiiij. for another. [George Gascoigne]