Night in the open.

Chronic, incurable.

I.e., when the mind is at ease, the body is sensitive to physical pain.

Thoroughly.

Generous.

Endure.

I.e., how shall your uncovedred heads and unfed bodies, your tattered rags full of holes, like windows in a house.

I.e., shake off the surplus you enjoy to the poor and show that the heavens distribute some kind of justice.

Poor Tom pretends he is taking soundings at sea in the heavy rains.

Poor Tom, pretending to be pursued by the devil, quotes snatches of old songs.

"Humh" signifies Poor Tom's shivering.

The devil tries to capture the souls of madmen by tempting them to suiside.

Chase.

"Do de" signifies Poor Tom's shivering.

Malign influences of planets and spirits.

Unnatural.

Lear notices the pins and splinters Edgar has stuck into his arm.

In legend, the pelican was supposed to feed its offspring with its own blood. The word pelican reminds Edgar of a children's rhyme.

As a favor from his mistress.

Slits or openenings in petticoats.

An interjection meaning something like "Off you go!"

Another line from an old ballad.

Civet cat (from which perfume was made).

Lear, Kent, and the Fool wear clothes.

Without the trappings of civilization.

Wicked.

Midnight.

Cataract.

Squints.

Nearly ripe.

Wold (open country).

Foals.

Begone.

A charm.

Water newt.

Salads.

Parish to parish.

Animals.

Begets.

Allow me.

Natural philosopher, scientist.

Lear in his madness takes Poor Tom for a learned man from Thebes, Athens, or Persia.

Avoid.

I beg your pardon.

Remain always.

Humor.

A candidate for knighthood.

This line may be from a lost ballad.

Motto, which absurdly comes from Jack the Giant Killer.

These explanations were taken from
King Lear. In The Norton Anthology of Literature. Ed. M.H.Abrams, et al. Vol I. Sixth Edition. New York: W.W.Norton & Company, 1993, pp 891-967.