Naked

adj. without clothing, nude; exposed; without covering, unprotected; unaided (such as the eye); not decorated, unadorned; invalid, without support (Law)

Nudity or nakedness is the state of wearing no clothing. It is sometimes used to refer to wearing significantly less clothing than expected by the conventions of a particular culture and situation, and in particular exposing the bare skin of intimate parts and has analogous uses.
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Adjective
1. completely unclothed; "bare bodies"; "naked from the waist up"; "a nude model"
(synonym) bare, au naturel(p), nude
(similar) unclothed
2. having no protecting or concealing cover; "naked to mine enemies"- Shakespeare
(synonym) defenseless
(similar) unprotected
3. (of the eye or ear e.g.) without the aid of an optical or acoustical device or instrument; "visible to the naked eye"; "clearly audible to the unaided ear"
(synonym) unaided
(similar) unassisted
4. devoid of elaboration or diminution or concealment; bare and pure; "naked ambition"; "raw fury"; "you may kill someone someday with your raw power"
(synonym) raw
(similar) overt, open

(a.)
Without pubescence; as, a naked leaf or stem; bare, or not covered by the customary parts, as a flower without a perianth, a stem without leaves, seeds without a pericarp, buds without bud scales.
  

(a.)
Without addition, exaggeration, or excuses; not concealed or disguised; open to view; manifest; plain.
  

(a.)
Unprovided with needful or desirable accessories, means of sustenance, etc.; destitute; unaided; bare.
  

(a.)
Not having the full complement of tones; -- said of a chord of only two tones, which requires a third tone to be sounded with them to make the combination pleasing to the ear; as, a naked fourth or fifth.
  

(a.)
Mere; simple; plain.
  

(a.)
Having no means of defense or protection; open; unarmed; defenseless.
  

(a.)
Having no clothes on; uncovered; nude; bare; as, a naked body; a naked limb; a naked sword.
  

When an option writer writes a call or put without owning the underlying asset.