Besides the so-called nomina sacra, which are described here, there are a number of other abbreviations which are common in minuscule Greek manuscripts, and which may be divided into two categories: signs which represent one or several letters (usually word endings) and which are added rather like diacritics (usually above the headline, but sometimes descending below it or written entirely below it, or attached to the preceding letter); and conventional signs which represent specific words or parts of words and are usually inserted into the line of script as if they were letters (these signs naturally may bear accents and breathings, as appropriate). The most common abbreviations in these two categories are gathered in the tables below for easy reference. If you want to read Byzantine manuscripts proficiently, you will need to put some effort into committing these to memory; but they do not need to be learned all at once before proceeding further. More complete lists of Byzantine abbreviations may be found in the plates in G. Cereteli's book on the subject (1904), where samples are shown in chronological order so that the development of the abbreviations may be observed; and in V. Gardthausen's Griechische Paläographie, second edition, vol. 2 (1913), pp. 335-352.
A. Abbreviations Representing Letters or Letter-Groups
Notes — α: The older of the two signs appears to be the simple horizontal line; since it was ambiguous (it could also represent final nu or indicate a nomen sacrum, or simply be a connecting stroke between two letters), dots were added on either side of it, which then themselves came to represent alpha. It would be unusual (though not unheard of) for both types to be used in close proximity, as in the illustration. — αι: Normally below the headline and attached to a preceding consonant, as here; but occasionally detached like a Latin "S" (especially in early minuscule). A very frequent instance of this abbreviation is και, where the abbreviation typically attaches to the lower oblique stroke of kappa and descends below the baseline from there. — αις: Almost always above the preceding letter. In many manuscripts there is not, in fact, a strict distinction between this abbreviation and that for εσ (which was pronounced identically); many scribes seem to write both abbreviations indifferently with one or two curls and with or without the dots — αν: Almost always above the preceding letter. This sign can be rotated clockwise so that the long stoke is horizontal, or counterclockwise so that it is vertical. The corner can become a curl so that the sign resembles a number "6", or it can be an angle so that it resembles an upper-case "L" (in which case it may be confused with εν). — αρ: This sign too can rotate considerably in all directions and is sometimes written in line with the letters; for examples see Cereteli's plate 3. — ασ: Almost always above the preceding letter or attached to it with a connecting stroke (especially in later, informal scripts) and/or written in a single stroke with a circumflex (especially in the word ἡμᾶς), which is reduced to a downward curve at the right end of the sign. — ειν: Always above the preceding letter; sometimes written with a hook at the upper end of both strokes (or of the lower one only), so that it resembles a repeated eta-nu abbreviation. — εισ: Almost always above the preceding letter. Occasionally written with only one "S" instead of two (in which case it may be identical to one of the forms of ησ, which indeed was pronounced identically). — εν: The two strokes may be of equal length, or of reversed length; the upper stroke may be vertical, but the lower one usually remains horizontal. Sometimes difficult to distinguish from αν. ερ: Sometimes protrudes above the headline; occasionally written entirely above the headline. εσ: Sometimes (perhaps originally) written without the two dots, whose function is to distinguish this abbreviation from an apostrophe. Often used interchangeably with the abbreviation for αισ (q.v.). — ην: The two strokes may be of equal or reversed length; in the latter case the stroke on the right may protrude well below the headline. As indicated, adding two dots to ην produces ιν (here again, the two were pronounced identically and are sometimes confused). — ησ: This abbreviation may take one of two shapes, which are identical to the two shapes of the abbreviation for the word και (see the table of word abbreviations below). Typically a given scribe will use exclusively one shape or the other, placing it above the line for ησ and in line for και. The second type may rotate up to 90 degrees clockwise. — ισ: This is simply the (first) abbreviation for ησ with two dots added above (again, the two were homophonous and are sometimes used interchangeably). οισ: Always above the headline; sometimes the loop is not closed. ον: Usually above the headline and often identital to a grave accent (so that the syllable -ὸν is abbreviated in a way which resembles a slanted equal sign, or even, sometimes, a horizontal [i.e. normal] equal sign); however, the abbreviation sometimes protrudes below the headline. οσ: Always above the headline (it would be an omikron if placed lower). In early minuscule, this sign is used indifferently for οσ and for ον; from about the 10th century onwards it is used for οσ exclusively. ου: The first type is in fact a ligature of the majuscule letters O and Υ, which is sometimes used in line. The second type is always above the headline (if lower, it would be an ypsilon). — ουσ: This is in fact the (second) abbreviation for ου with an added lunate sigma. Normally placed above the headline, with the tail swooping down below it. — ω· Always entirely above the headline (whereas ωσ often swoops down on the right). — ων: Identical in shape to a circumflex, but usually larger. When doubled, it is to be read ῶν. — ωσ: Usually begins above the headline but very often finishing well below it on the right (unlike the ω abbreviation).
B. Abbreviations Representing Words or Parts of Words
Notes — ἀπο: In most scripts this abbreviation is identical to the letter sequence υγ; however, when breathings are present, there is never ambiguity because upsilon can never carry a smooth breathing. — γαρ: A barred gamma. Barring as a sign of abbreviation is generally not terribly common in Byzantine manuscripts, with a few exceptions, including γαρ and also κατα (below). Of course, γαρ may also be written by adding the αρ abbreviation to gamma. — δε: Sometimes two dots are added above. In addition, since δε nearly always carries a grave accent, the accent was sometimes taken to be part of the abbreviation, so that you will occasionally find two grave accents, or even a grave and an acute together over this sign. — δια: The squiggle under the letter is actually a generic abbreviation indicator, used (with different values) also in ουν and -μενος (as well as in other less common abbreviations). The delta in the abbreviation may be of majuscule shape, even when the surrounding script is minuscule. — ειναι: The sign may extend below the baseline, and it be rotated 90 degrees counterclockwise, so that it resembles the abbreviation for ω, especially when the dots are omitted, as they occasionally are; for other variants, see Cereteli's plate 7.— εισι(ν): This is simply a doubling of the (second) εστι abbreviation; as in the latter, the long strokes (or one of them) may have a short hook descending from the top.— εστι(ν): In the first type, the ascending stroke may have a loop at the bottom, like the left part of a minuscule epsilon. The second type may have a hook descending from the top. — ηγουν: This is an eta with a stylized gamma over it. The stylized gamma typically looks exactly like the abbreviation for ωσ in ligature with an acute accent. Amusingly, as a result of misunderstanding this abbreviation, one of the most important early editions of Sophocles, that of Turnebus (pubished in Paris in 1553), prints the nonsense word Ηως wherever the word ἤγουν appears in the scholia (there are several examples, e.g., in the first lines of this page, where you might also enjoy looking for other abbreviations and ligatures as they were reproduced in sixteenth-century typography). — -ικος, -ικον etc.: The squiggle in fact represents kappa and is occasionally used also for other endings involving this letter (as you can see in Cereteli's plates 13 & 14); but the most common use of it is for the ending -ικος (-η, ον). — και: Besides kappa with the sign for αι attached, the two most common ways of abbreviating this word are shown here. The second type may be rotated 90 degrees clockwise. See the notes above on the abbreviation for ησ. — κατα: A barred kappa with a "superscript" tau. — -μενος, μενον etc.: Cf. the note above on δια. — οτι: Very occasionally the dots are omitted and/or the sign is rotated to various angles. — ουν: Cf. above the note on δια. This sign is used not only for the word οὖν but also, sometimes, in other words containing the letter sequence ουν (e.g. δοῦναι, δηλοῦν, etc.) — παρα: the sign above the pi, which looks vaguely like a rotated majuscule epsilon, is actually an old tachygraphic sign for αρα and is very occasionally used in its own right to represent the word ἄρα. Since the preposition περι is sometimes abbreviated by suspension by writing an actual epsilon above a pi, there is considerable scope for confusing these two prepositions. — προσ: Easily confused with late types of majuscule epsilon, which however (unlike the abbreviation) typically do not extend above the headline. Rarely used after the reintroduction of majuscule letters.