adj

• (obsolete) Lonely; solitary; desolate.
  "I recche not how longe that ye stryve; / Lat ech of hem be soleyn al hir lyve,"
• (obsolete) Mischievous; malignant; unpropitious.
  "Such sullen planets at my birth did shine, / They threaten every Fortune mixt with mine."
• (obsolete) Obstinate; intractable.
  "Things are as sullen as we are, and will be what they are whatever we think of them."

noun

• (archaic) One who is solitary, or lives alone; a hermit.
  "He sit neither with seint Johan, / Symond ne Jude, / Ne with maydenes ne with martires, / Confessours ne wydewes; / But by hymself as a soleyn, / And served on erthe."
• (in the plural) Sullen feelings or manners; sulks; moroseness.
  "And let them die that age and sullens have;"

verb

• (obsolete) To make sullen.
  "The idle man is like the dumb jack in a virginal: while all the other dance out a winning music, this, like a member out of joint, sullens the whole body, with an ill disturbing laziness."