[  Reference Info Index  ]

Like any other specialized item, the fountain pen has amassed a lexicon of terms that are unique. And like other jargon languages, fountain pen jargon can be cryptic or confusing. This glossary presents brief definitions for many of the most common pen terms. It is not complete (an impossible goal); but it is a work in progress, and I welcome suggestions for terms to add. (Revised July 5, 2010)

The glossary is organized alphabetically. For numbers, look under the spelled-out form; e.g., for 14K, look under fourteen.

If there is a magnifying-glass symbol () next to an image, click the magnifying glass to view a zoomed version for more detail.

O
oblique	A nib shape that is ground so that the writing tip contacts the paper properly when the pen is rotated in the user’s hand. Obliques are made in left- and right-foot shapes, and there are variations in the angle at which the tip is finished. The left-foot oblique (shown here, and so named because the angled tip resembles the shape of a person’s left foot) is the most common style. A left-foot oblique requires counterclockwise rotation of the pen so that the nib, instead of facing straight upward, is leaning toward a right-handed writer or away from a left-handed writer. Most modern obliques are ordinary round nibs, not designed to produce line variation (illustrated near right). An oblique italic nib, which is designed to produce line variation, has a wide thin tip cut at an angle across, to create broad strokes in one direction (at a slight angle to the nib itself) and very thin strokes in the orthogonal direction. A crisp oblique italic nib (illustrated far right) is relatively lacking in smoothness but produces greater line variation than a cursive oblique italic, which is ground to be relatively smooth in use. Read a tutorial on nibs here. See also cursive, italic, nib, offset pen, Relief, reverse oblique, and stub.
Octanium	Parker’s trade name for the stainless steel used to make nibs for the company’s lower-priced pens; so called because the alloy contains eight elements (40% Co, 20% Cr, 15% Ni, 15% Fe, 7% Mo, 2% Mg, trace Be, trace C). Used from 1948 into the 1950s.
offset pen	(also offset nib; among dip-pen calligraphers, oblique nib) A flexible dip pen nib, usually steel, made with a pronounced offset in its body (illustrated to the right) so that the pen itself will be pointing upward and to the right when the penholder is oriented toward 12 o'clock relative to the paper; used to create line variation in copperplate and round hand scripts. See also dip pen, holder, nib (historical note), steel pen.
Old English	See Blackletter.
olive ripple	See ripple.
One-Shot	See Vacuum-Fil (definition 1).
1000	See Sheaffer numbers.
Onoto the Pen	A long-lived series of pen models produced by printer/stationer Thomas De La Rue & Co., of England. In 1906, De La Rue entered the pen market with a self-filling fountain pen that it named Onoto the Pen for the name’s euphony and, because Ohoto is not a real word, the lack of need to translate it into foreign languages. The pen’s innovative pneumatic filler, invented by a tinkerer and vaudeville performer named George Sweetser, flushes the pen and refills it in a single out-and-in cycle of a barrel-length plunger and was the prototype for similar fillers produced by Sheaffer, Wahl-Eversharp, and Conklin during the 1930s. Shown here is a very early straight-cap Onoto. See also De La Rue; Vacuum-Fil (definition 1).
open nib	Retronym indicating a nib that is exposed to view; the type commonly seen. Until the advent of the hooded nib on the Parker “51”, the term was unnecessary. See also hooded nib, Inlaid Nib™, nib, “TRIUMPH” point.
O-ring	A gasket made of a natural or synthetic elastomer (e.g., Buna-N or Viton®, having a circular cross-section (similar in shape to a “cake” doughnut), designed to be lightly compressed between two surfaces to make a seal. Patented in 1939 (U.S. Patent Nº 2,180,795) and coming into wide use during World War II, when the U.S. government declared it a critical war resource, the O-ring is now nearly ubiquitous where a circular seal is needed. In pens, it is frequently used to seal between the barrel and section to allow use as an eyedropper filler. Sheaffer used O-rings for the sliding seal in its Touchdown and Snorkel pens.
OS	(also O/S) See oversize.
osmalloy	An alloy containing osmium, used by Sheaffer beginning in 1944 for tipping “TRIUMPH” point nibs. See also osmium. “TRIUMPH” point.
Osmiridium	A naturally occuring alloy of osmium and iridium, usually with trace amounts of one or more other platinum-group metals, used for tipping nibs. See also iridium, osmium, tipping material.
Osmiroid	A pen manufacturing company located in Gosport, England. Founded in London in 1824 by James Perry, the company (then known as Perry & Co.) pioneered the manufacture of high-quality steel pens. Using Perry’s patented design, it became a world force in the market, rivaling Esterbrook with sales of its Iridinoid and Osmiroid nibs. After World War II, Perry (then E. S. Perry Ltd) developed its first fountain pen, the Osmiroid 65, and subsequently relocated to Gosport. The 65 (shown below) is a lever filler; its design includes what became Osmiroid’s trademark feature, user-interchangeable nibs that are compatible with the Esterbrook Renew-Point. The company officially changed its name to Osmiroid in 1987. It was acquired by Berol in 1989, and manufacture ceased in 1991. The name is now owned by a manufacturer whose cheap Chinese-made products are not compatible with, or equal in quality to, those of British manufacture. See also Esterbrook, Renew-Point, steel pen.
osmium	A brittle blue-gray metal of the platinum group, used in nib tipping material alloys because of its hardness. See also tipping material.
ossify	(also petrify; said of the rubber sac in any pen using a sac as an ink reservoir) To harden due to the chemical action of ink. Ossification is a slow process; a pliable sac becomes progressively more leathery and then stiff, to the point that when squeezed it will shatter into shards with shiny edges that give the appearance of broken glass. An ossified sac is typically strong enough to resist the squeezing action of the lever in a lever-filling pen; attempts to operate the lever in a pen with an ossified sac usually result in serious damage to the lever or the lever box (if present). See also lever box.
Osthenium	(also Osithenium) An alloy of osmium and ruthenium, with trace amounts of one or more other platinum-group metals; used by Eversharp for tipping Ventura nibs. See also osmium, ruthenium, tipping material, Ventura.
overfeed	A feed that lies along the upper surface of the nib instead of within the curve of the under surface; used mostly during the 19th century. Shown here is an H. M. Smith “Rival” pen, c. 1895, with an overfeed. See also feed, over-under feed. Do not confuse the reinforcing projection on the upper surface of the Parker 180’s nib with a true overfeed.
overlay	1  A decorative covering of (usually) precious metal, made of sheet or tube, typically with decorative cutouts or engraving, or both. The pen shown here has a gold-filled (rolled gold) overlay with an embossed pattern resembling chasing.  2  Colloquialism for a pen so decorated. See also Continental, half overlay, LEC.
oversize	(also Oversize; abbreviated OS or O/S) A pen that is larger than the “standard” size. Various companies used specific model names such as Maxima (Parker) or Premier (Sheaffer, shown below, 1933 Premier Balance and “standard” Balance) to designate their oversize pens. See also giant, Magnum, Maxima.
over-under feed	(also double feed, dual feed) A double feed, with parts that lie both along the upper surface of the nib and within the curve of the under surface; used mostly during the 1890s and the first decade of the 20th century, and advertised as providing superior reliability. At first glance, an over-under feed can easily be mistaken for a plain overfeed. See also feed, overfeed.
overwriter	A left-handed person who positions his or her hand and the paper so that the hand passes across the paper above (over) the line being written, as shown below. See also underwriter.
Oxford	(also Wahl-Oxford) A Wahl-Eversharp sub-brand (introduced 1931). Early Oxford pens (illustrated below, upper) featured 14K nibs and have the same shape as the contemporaneous (and more expensive) Equi-Poised model; later models are more cheaply made and are much less elegant (below, lower). Eventually, pens with steel nibs were added to the line.
oxidation	See ambering, discoloration.

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