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English

arcsine

|ark-sine|

C1

🇺🇸

/ˈɑɹk.saɪn/

🇬🇧

/ˈɑːk.saɪn/

inverse of sine

Etymology
Etymology Information

'arcsine' originates from Modern English, specifically the combination of the words 'arc' and 'sine', where 'arc' meant 'a circular arc' (from Latin 'arcus') and 'sine' referred to the trigonometric sine (from Latin 'sinus').

Historical Evolution

'sine' changed from Sanskrit 'jya-' (via Arabic 'jayb') into Latin 'sinus', and later became the mathematical term 'sine' in European languages; 'arc' comes from Latin 'arcus' via Old French 'arc'; these elements were combined in Modern English to form 'arcsine' to denote the inverse of the sine function.

Meaning Changes

Initially, Latin 'sinus' meant 'bay' or 'fold', but over time it came to denote the trigonometric sine; combining 'arc' and 'sine' produced 'arcsine', which now specifically means 'the inverse of the sine function' in mathematics.

Meanings by Part of Speech

Noun 1

the inverse trigonometric function of the sine; denoted arcsin or sin⁻¹, which returns the angle whose sine is a given number.

The arcsine of 0.5 is π/6.

Synonyms

Noun 2

an angle whose sine is a specified number (often used when the number is in the range [-1, 1]).

Find the arcsine of -1: the arcsine of -1 is -π/2.

Synonyms

Last updated: 2025/10/09 09:29