Circumflex in the context of "Ĵ"

A diacritic (also diacritical mark, diacritical point, diacritical sign, or accent) is a glyph added to a letter or to a basic glyph. The term derives from the Ancient Greek διακριτικός (diakritikós, "distinguishing"), from διακρίνω (diakrínō, "to distinguish"). The word diacritic is a noun, though it is sometimes used in an attributive sense, whereas diacritical is only an adjective. Some diacritics, such as the acute ⟨ó⟩, grave ⟨ò⟩, and circumflex ⟨ô⟩ (all shown above an 'o'), are often called accents. Diacritics may appear above or below a letter or in some other position such as within the letter or between two letters.

The main use of diacritics in Latin script is to change the sound-values of the letters to which they are added. Historically, English has used the diaeresis diacritic to indicate the correct pronunciation of ambiguous words, such as "coöperate", without which the <oo> letter sequence could be misinterpreted to be pronounced /ˈkuːpəreɪt/. Other examples are the acute and grave accents, which can indicate that a vowel is to be pronounced differently than is normal in that position, for example not reduced to /ə/ or silent as in the case of the two uses of the letter e in the noun résumé (as opposed to the verb resume) and the help sometimes provided in the pronunciation of some words such as doggèd, learnèd, blessèd, and especially words pronounced differently than normal in poetry (for example movèd, breathèd).

In mathematics, a unit vector in a normed vector space is a vector (often a spatial vector) of length 1. A unit vector is often denoted by a lowercase letter with a circumflex, or "hat", as in ${\displaystyle {\hat {\mathbf {v} }}}$ (pronounced "v-hat"). The term normalized vector is sometimes used as a synonym for unit vector.

The normalized vector û of a non-zero vector u is the unit vector in the direction of u, i.e.,

Caret (from Latin caret 'there is lacking') is the name used familiarly for the character ^ provided on most QWERTY keyboards by typing ⇧ Shift+6. The symbol has a variety of uses in programming and mathematics. The name "caret" arose from its visual similarity to the original proofreader's caret, ‸, a mark used in proofreading to indicate where a punctuation mark, word, or phrase should be inserted into a document. The ASCII standard (X3.64.1977) calls it a "circumflex"; the Unicode standard calls it a "circumflex accent", although it is no longer practicable for that purpose.

In Ancient Greek grammar, a perispomenon (/pɛrəˈspɑːməˌnɑːn/ peh-rə-SPAW-mə-NAWN; Ancient Greek: περισπώμενον perispṓmenon) is a word with a high-low pitch contour on the last syllable, indicated in writing by a tilde diacritic (◌̃) or an inverted breve accent mark (◌̑) in native transcriptions with the Greek alphabet, or by a circumflex accent mark (◌̂) in transcriptions with the Latin alphabet. A properispomenon has the same kind of accent, but on the penultimate syllable.

Inverted breve or arch is a diacritical mark, shaped like the top half of a circle ( ̑ ), that is, like an upside-down breve (˘). It looks similar to the circumflex (ˆ), which has a sharp tip (Â â Ê ê Î î Ô ô Û û), while the inverted breve is rounded: (Ȃ ȃ Ȇ ȇ Ȋ ȋ Ȏ ȏ Ȗ ȗ).

Inverted breve can occur above or below the letter. It is not used in any natural language alphabet. It is identical in form to the Ancient Greek circumflex.