Ur-

WordReference Random House Unabridged Dictionary of American English © 2026

uro-,¹ 

1. a combining form meaning "urine,'' used in the formation of compound words:
   urology.

Also,[esp. before a vowel,] ur-. 

• Greek, combining form of oûron urine

uro-,² 

1. a combining form meaning "tail,'' used in the formation of compound words:
   uropod.

Also,[esp. before a vowel,] ur-. 

• Neo-Latin ūro-, combining form representing Greek ourá

WordReference Random House Unabridged Dictionary of American English © 2026

Ur  (ûr, ŏŏr), n. 

1. Ancient History, Archaeology, Place Names an ancient Sumerian city on the Euphrates, in S Iraq: extensive excavations, esp. of royal tombs.

ur-¹ :

1. var. of uro- ¹ :
   uranalysis.

ur-² :

1. var. of uro- ² before a vowel:
   urite.

ur-³ , (sometimes cap.)

1. a combining form meaning "earliest, original,'' used in words denoting the primal stage of a historical or cultural entity or phenomenon:
   ur-civilization; urtext.

• German ur-, Middle High German, Old High German; cognate with Old English or-

Collins Concise English Dictionary © HarperCollins Publishers::

ur- combining_form

1. a variant of uro-1