A Miltonic sonnet is a fourteen-line sonnet written in the style of John Milton, usually with the more flexible syntax, heavy enjambment, and thoughtful, argumentative movement found in his own sonnets. It often keeps the broad sonnet shape but avoids the neat, closed-off feel of many Shakespearean sonnets, letting the sentence flow across line breaks and even through the octave and sestet.
Writers use the term to describe sonnets that feel more fluid, less epigrammatic, and more closely tied to Milton's manner than to a fixed rhyme pattern alone.
Example
When winter thins the daylight to a thread,
I walk where bare trees sketch the iron sky,
And think how grief, though buried, will not die
But rises with each name the living said,
Till memory, like frost, creeps through the mind
And leaves its silver lesson line by line;