Tyrannosaurus rex
tie-RAN-oh-SAW-rus RECKS
Genus and species
king of the tyrant lizards
Literally: tyrant lizard king
Tyrannosaurus · genus
| Part | Meaning | Language | Note |
|---|---|---|---|
| Tyrann- | absolute ruler, tyrant | Greek (tyrann, -o) | from Greek tyrannos; combining form tyrann- / tyranno- |
| -o- | connecting vowel | Greek connecting vowel between roots | |
| -saurus | lizard | Greek (saur, -o, =us) | terminal form -saurus (=us ending); masculine gender |
rex · specific epithet
| Part | Meaning | Language | Note |
|---|---|---|---|
| rex | king | Latin | Latin nominative singular; noun in apposition to the genus name |
Tyrannosaurus is a New Latin compound of two Greek roots joined by the connecting vowel -o-. It is a masculine noun (gender from -saurus = -us). The specific epithet rex is a Latin noun in apposition (not an adjective), so it does not inflect to agree with the genus in ending — it simply sits beside it as 'king'. Together they read 'Tyrannosaurus [that is] rex'.
Pronunciation
- tie-RAN-oh-SAW-rus Antepenult stress: the penult vowel 'au' is a diphthong (au = 'aw'), which would normally pull stress to the penult — however in common/traditional palaeontological usage the stress falls on the antepenult syllable RAN, treating the -o- as a connector and -saurus as a transparent suffix. By strict rule the diphthong 'au' in the penult stresses the PENULT (tie-ran-oh-SAW-rus); this is also widely used and is given as the primary form here.
- RECKS Two-syllable rule does not apply (one syllable); single-syllable word, fully stressed.
Commonly: tie-RAN-oh-SOR-us RECKS (common spoken form, collapsing 'au' toward a short 'o')
Other readings
Tyrannos + saurus with no connecting vowel is not found; the -o- connector is standard for Greek compounds.
'tyrann' and 'saur' were both confirmed in the dictionary. 'rex' was confirmed in the dictionary as Latin for 'king'. -saurus is the terminal (=us) form of the root saur-, standard for theropod genera. The diphthong 'au' in -saurus strictly triggers penult stress (tie-ran-oh-SAW-rus); the colloquial reduction to -SOR- is extremely common in English speech. Coined by H.F. Osborn, 1905.