A metal shirt collar, nine rows of pearls, two bands of steel: fashion's neckwear is easier to understand when we look beyond the label.
Elsa Schiaparelli made a necklace that looks as though a shirt has vanished from beneath it. Dated around 1937, the piece curves around the neck in gold-colored metal, then opens at the front into two long points. The familiar geometry of a clothing collar survives. The cloth does not.

The Metropolitan Museum of Art catalogs it as Necklace. Its accompanying text says the object also "looks like and functions as a collar".
Both descriptions hold. As jewelry, it is a separate ornament; as a collar, it supplies a line we expect clothing to provide. The confusion begins when we assume those roles must be mutually exclusive.
In short: A necklace identifies the object as jewelry; a choker emphasizes its close proximity to the neck; and a collar highlights its structural role as a garment component that frames the silhouette. These terms overlap to describe different aspects of the same piece.
So when does a necklace become a collar? Schiaparelli's piece suggests that it can start behaving like one without ceasing to be jewelry. Add choker, which draws attention to how closely something sits around the neck, and we have three words that can describe different aspects of the same object.
A collar could be an engineering problem
In late-sixteenth- and early-seventeenth-century European dress, a collar could organize the space around the head and shoulders. The form now called a Medici collar rose behind the head and along the sides, leaving the front open above a low neckline. Wire or heavy starch supported its lace or light fabric. Even its name is retrospective: FIT's Fashion History Timeline notes that the term was applied during eighteenth- and nineteenth-century revivals.

The rebato, another standing lace collar of the period, depended on a support that held it away from the body. After 1600, rebato could refer to that supporting framework itself. A fashion term could name the engineering underneath the lace.

The seventeenth-century falling band took a different position: broad and flat, often edged in lace, it rested on the shoulders. It could be stitched to a shirt or doublet, or tied on and removed for laundering.
That removable detail matters. Detachment alone did not turn it into jewelry. Its relationship to the shirt, shoulders, and neckline still belonged to dress. These examples make "collar equals a wide choker" an inadequate explanation: width is only one part of the story.

Nine rows of pearls around the neck
A collar-like form could also be built from jewelry materials. René Lalique's Aubépines choker, circa 1902-1904, joins nine rows of pearls with a central plaque of enamel hawthorn leaves and pearl fruit. The plaque follows the curve of the neck.
Musée Lalique describes collier de chien, literally "dog collar," as one French term for a choker necklace. Here the name describes a neck-encircling form realized in gold, enamel, and pearls. It does not make the object something other than jewelry.

More unexpectedly, the museum explains that this type could be worn with a low neckline or over a high one. Closeness to the neck did not necessarily mean contact with bare skin. Over clothing, the pearl rows would occupy the garment's surface; above a low neckline, they would create their own band around the exposed neck. The same construction allows two different relationships to dress.
Nor should necklace be taken to mean "long". In its account of European fashion in the 1790s, FIT describes necklaces as including "a variety of chokers and long chain necklaces". Short and long were both within the necklace family. A choker could be a kind of necklace, rather than its opposite.
A close fit does not settle the meaning
Material and context can change what close-worn neckwear communicates. The Museum at FIT's exhibition A Queer History of Fashion describes a significant gay leatherman culture emerging in the 1970s, particularly in San Francisco and New York, where certain leather garments signaled an interest in sadomasochism and sex play. A later ensemble in the exhibition, dated circa 2005, includes a choker alongside chaps and wrist cuffs.
Within that ensemble, the neck object participates in a specific cultural language. The word choker by itself cannot convey all of it, and neither can it assign that meaning to every close-worn band.

Claude Montana's spring 1979 leather jumpsuit also appears in the exhibition, whose caption describes his introduction of erotic street-style leather into high fashion. Around 1990, the Montana ready-to-wear label produced a steel collier de chien now held by Palais Galliera: two metal bands articulated at the back, with two half-buckles forming a motif at the front.
Set beside Lalique's pearls, the steel and buckle shapes give the collar form a different visual vocabulary. Yet both objects can be described as jewelry. Their shared closeness to the neck tells us much less than their materials, construction, and presentation do. It certainly cannot tell us who the wearer is.

What each word makes visible
Aphros's reading is to treat these terms as overlapping lenses, not an official industry taxonomy.
Necklace directs attention to the object as jewelry or ornament. It leaves considerable room for different lengths, materials, and structures.
With choker, the emphasis moves to proximity: how closely the object encircles the neck. A narrow ribbon and several rows of pearls can share that relationship while occupying very different amounts of space.
Collar brings the neckline and silhouette into the discussion. The word can describe an actual garment component, but in jewelry it can also suggest an object that frames the neck or supplies a clothing-like structure. Those uses overlap without becoming identical.
For someone describing or choosing a piece, this makes the compound choker necklace quite intelligible: one word locates the object on the body, the other identifies it as ornament. Collar necklacecan likewise draw attention to a jewelry object's framing shape. Neither phrase guarantees a particular width, stiffness, or fit.
A product name is a starting point. A worn view tells you whether a piece circles the middle of the neck, rests at its base, or extends toward the collarbones. Dimensions reveal how much space it occupies. Construction tells you whether it hangs as a chain, wraps as a flexible band, or holds an open curve. Two pieces photographed at the same height can behave very differently once worn.
When ornament changes the neckline
Schiaparelli's two points make sense of this overlap. Calling the piece a necklace identifies it as jewelry, but misses the joke. Calling it a collar brings the points into focus: the object supplies a recognizable fragment of clothing without the rest of the garment. The Met connects this conflation of forms with Schiaparelli's Surrealist influences.
Its collar effect depends on more than placement. The breadth of the band gives it a surface, rather than the fine line of a chain. The metal preserves an outline associated with folded cloth. Its open front makes the space between the points part of the design. In an outfit, the surrounding neckline would further change how that outline reads.
This is also the territory Aphros explores through ARCH: Midnight Patent Collar. ARCH's narrow black band has a high-gloss patent PU exterior. Seen through Aphros's body-architecture perspective, its close placement makes the interval between jaw, neck, and garment neckline part of the composition. With an open shirt, the band can introduce a separate horizontal edge above the shirt's opening. Its small scale does not prevent it from affecting the silhouette.
A neck object can supply the edge an outfit leaves unfinished. Once we notice that, we can choose it for the neckline it creates, rather than only for the category in which it is sold.