# perpendicular
## English
### Etymology

Derived from Middle French perpendiculaire, from Old French perpendiculer, from Latin perpendiculum (“plumb line”).

### Pronunciation

* (UK) IPA: /ˌpɜː.pənˈdɪk.jə.lə(ɹ)/ enPR: pû"pəndĭ'kyələ(r),
* (US) IPA: /pɝ.pɛnˈdɪk.ju.lɚ/, /pɝ.pənˈdɪk.jə.lɚ/
* Audio (US):(file)
* Rhymes: -ɪkjʊlə(ɹ)

### Adjective

perpendicular (comparative more perpendicular, superlative most perpendicular)
* (geometry) At or forming a right angle (to something).
    Synonyms: normal, orthogonal
    In most houses, the walls are perpendicular to the floor.
** 2012 March, Henry Petroski, “Opening Doors”, in American Scientist‎, volume 100, number 2, pages 112–3:A doorknob of whatever roundish shape is effectively a continuum of levers, with the axis of the latching mechanism—known as the spindle—being the fulcrum about which the turning takes place. Applying a force tangential to the knob is essentially equivalent to applying one perpendicular to a radial line defining the lever.
* Exactly upright; extending in a straight line toward the centre of the earth, etc.
* Independent of or irrelevant to each other; orthogonal.
** 2019 May 31, David M. Willis, “Wrangled”, in Dumbing of Age:Hey, I'm not unsabotaging anything! This is completely perpendicular sabotage!

#### Derived terms

* perpendicular axis theorem
* perpendicularity
* perpendicularly
* perpendicularness
* perpendicular pronoun
* perpendicular recording
* perpendicular universe
* quasiperpendicular

#### Translations
### Noun

perpendicular (plural perpendiculars)
* (geometry) A line or plane that is perpendicular to another.
* A device such as a plumb line that is used in making or marking a perpendicular line.
* (obsolete, slang) A meal eaten at a tavern bar while standing up.

#### Translations
### See also

* ⟂ (This symbol can be pronounced “perp” when used as a subscript of a letter representing a vector.)

## Catalan
### Etymology

Borrowed from Late Latin perpendiculāris, from perpendiculum.

### Pronunciation

* IPA: (Central) [pər.pən.di.kuˈlar]
* IPA: (Balearic) [pər.pən.di.kuˈla]
* IPA: (Valencia) [peɾ.pen.di.kuˈlaɾ]

### Adjective

perpendicular m or f (masculine and feminine plural perpendiculars)
* perpendicular

#### Derived terms

* perpendicularment

### Noun

perpendicular f (plural perpendiculars)
* perpendicular

### Further reading

* “perpendicular” in Diccionari de la llengua catalana, segona edició, Institut d’Estudis Catalans.
* “perpendicular”, in Gran Diccionari de la Llengua Catalana, Grup Enciclopèdia Catalana, 2025
* “perpendicular” in Diccionari normatiu valencià, Acadèmia Valenciana de la Llengua.
* “perpendicular” in Diccionari català-valencià-balear, Antoni Maria Alcover and Francesc de Borja Moll, 1962.

## Portuguese
### Etymology

Borrowed from Late Latin perpendiculāris, from perpendiculum.

### Pronunciation

* (Brazil) IPA: /peʁ.pẽ.d͡ʒi.kuˈlaʁ/ [peh.pẽ.d͡ʒi.kuˈlah]
* (Brazil) IPA: /peʁ.pẽ.d͡ʒi.kuˈlaʁ/ [peh.pẽ.d͡ʒi.kuˈlah]
** (São Paulo) IPA: /peɾ.pẽ.d͡ʒi.kuˈlaɾ/
** (Rio de Janeiro) IPA: /peʁ.pẽ.d͡ʒi.kuˈlaʁ/ [peχ.pẽ.d͡ʒi.kuˈlaχ]
** (Southern Brazil) IPA: /peɻ.pẽ.d͡ʒi.kuˈlaɻ/
* (Portugal) IPA: /pɨɾ.pẽ.di.kuˈlaɾ/
* (Portugal) IPA: /pɨɾ.pẽ.di.kuˈlaɾ/
** (Southern Portugal) IPA: /pɨɾ.pẽ.di.kuˈla.ɾi/
* Hyphenation: per‧pen‧di‧cu‧lar

### Adjective

perpendicular m or f (plural perpendiculares)
* perpendicular

### Noun

perpendicular f (plural perpendiculares)
* perpendicular

#### Derived terms

* perpendicularidade
* perpendicularmente

## Romanian
### Etymology

Borrowed from French perpendiculaire.

### Noun

perpendicular f (plural perpendiculare)
* perpendicular

#### Declension
## Spanish
### Etymology

Borrowed from Late Latin perpendiculāris, from perpendiculum.

### Pronunciation

* IPA: /peɾpendikuˈlaɾ/ [peɾ.pẽn̪.d̪i.kuˈlaɾ]
* Rhymes: -aɾ
* Syllabification: per‧pen‧di‧cu‧lar

### Adjective

perpendicular m or f (masculine and feminine plural perpendiculares)
* perpendicular

#### Derived terms

* perpendicularmente

### Further reading

* “perpendicular”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8, Royal Spanish Academy [Spanish: Real Academia Española], 2024 December 10