• (GA) enPR: ärch, IPA: /ɑɹt͡ʃ/
• (RP) IPA: /ɑːt͡ʃ/
• (by analogy to arc, nonstandard) IPA: /ɑɹ˞k/, /ɑːk/

arch (plural arches)

1. An inverted U shape.
2. An arch-shaped arrangement of trapezoidal stones, designed to redistribute downward force outward.
3. (architecture) An architectural element having the shape of an arch
4. Any place covered by an arch; an archway.

   to pass into the arch of a bridge

5. (archaic, geometry) An arc; a part of a curve.
6. A natural arch-shaped opening in a rock mass.
7. (anatomy) Curved part of the bottom of a foot.

• French: arc, arche
• German: Bogen
• Portuguese: arco
• Russian: дуга́
• Spanish: arco

• German: Bogen
• Portuguese: arco
• Russian: а́рка
• Spanish: arco

• French: arc
• German: Bogen
• Italian: arco
• Portuguese: arco
• Russian: а́рка
• Spanish: arco

• Russian: свод
• Spanish: puente

arch (arches, present participle arching; past and past participle arched)

1. To form into an arch shape

   The cat arched its back

2. To cover with an arch or arches.

• Portuguese: arquear
• Russian: изгиба́ться дуга
• Spanish: arquear

arch (comparative archer, superlative archest)

1. Knowing, clever, mischievous.

   I attempted to hide my emotions, but an arch remark escaped my lips.

   • [He] spoke his request with so arch a leer.

   • 1912 January, Zane Grey, chapter 3, in Riders of the Purple Sage: A Novel, New York, N.Y.; London: Harper & Brothers Publishers, OCLC 6868219 ↗:

     Lassiter ended there with dry humor, yet behind that was meaning. Jane blushed and made arch eyes at him.

2. Principal; primary.
   • c. 1593, William Shakespeare, “The Tragedy of Richard the Third: […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358 ↗, [Act IV, scene iii]:

     the most arch act of piteous massacre

   They were arch enemies.

• Portuguese: esperto
• Russian: игри́вый
• Spanish: pícaro

• Spanish: principal

arch (plural arches)

1. (obsolete) A chief.
   • c. 1593, William Shakespeare, “The Tragedy of Richard the Third: […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358 ↗, [Act IV, scene iii]:

     My worthy arch and patron comes to-night.

• arc

arch (not comparable)

1. (statistics) Initialism of autoregressive conditional heteroskedasticity

1. A male given name.