Sic semper tyrannis

John Wilkes Booth is said to have uttered the words "sic semper tyrannis" immediately after he shot Abraham Lincoln.  The meaning is "Thus always to tyrants".  Tyrannis is the dative plural of tyrannus, -i (m).

Another famous phrase incorporating a dative plural is "Vae victis", which means "Woe to the vanquished".

vae  interj.  woe, alas

O quam cito transit gloria mundi

O quam cito tranist gloria mundi is a phrase in the The Imitation of Christ by Thomas a Kempis.  It means "Oh, how quickly passes the glory of the world."

A related and rather better known phrase is sic transit gloria mundi, which means "Thus passes the glory of the world."  A variation on that phrase occurs at the end of the science fiction novel A Canticle for Leibowitz.  When the last monk enters the space ship, he pauses in the open hatchway and says sic transit mundum, which means "Thus passes the world".

cito  adv  quickly, soon
sic  adv  thus

Ardens sed virens

Ardens sed virens is another motto which relates to the burning bush in chapter 3 of Exodus.  In this case, it is the motto of Presbyterian Church in Ireland and is translated as burning but flourishing.

Ardens and virens are both present participles.  They decline like third declension adjectives ending in -ns

ardeo, ardere, arsi, arsum  (2nd)  to burn, to be on fire

vireo, virere, virui  (2nd)  to be green, to flourish

Nec tamen consumebatur

Nec tamen consumebatur is the motto of the Church of Scotland.  It means: yet it was not consumed and is an allusion to the burning bush in Exodus chapter 3, verse 2.

nec / neque  adv  not; conj  and not, but not

tamen  adv  however, nevertheless

consumo, -ere, -psi, -ptum  to consume, to eat up, to waste

consumebatur  3rd person singular imperfect passive of consumo

Cave canem and caveat emptor

Both cave in cave canem and caveat in caveat emptor can be translated as beware, and both are forms of the verb of  the second conjugation verb caveo, cavere, ...  However, the two words are very different - the one an imperative and the other a subjunctive:

cave  singular imperative
caveat  3rd person singular present active subjunctive

Turning to the meaning of these phrases, cave canem is, of course, beware of the dog;  Caveat emptor means let the buyer beware.

emptor, emptoris  (m) buyer

Hopefully, that's clear, but how would you say: beware of the buyer?

I.H.S.

Graveyards are often a good place to find Latin inscriptions.  The other day I was wandering through one, when I noticed a tall tombstone with the letters I.H.S. standing out from the top part of the cross.  I assumed that they must mean: in hoc signo vinces (In this sign you conquer). 

Anyway, I looked them up on wikipedia and found the real position is more complicated.  The three letters are more likely to be the Greek letters iota, eta and sigma.  Alternatively, if they are Latin then they may stand for Iesus hominum salvator (Jesus saviour of men).  In either case, they are probably a Christogram.

Cogita mori!

"Cogita mori" is the inscription on a 16th century vanitas ring recently found near the city of Dunfermline by a Dundee metal detector enthusiast.  The skeleton ring is currently being assessed by the Treasure Trove Unit in Edinburgh, but it is hoped that it will be put on display in Dunfermline.  The inscription means: remember death.

Cogita is the imperative active singular of the verb cogito, -are, -avi, -atum, which means: to think.

Mori is the first person singular perfect of the deponent vert morior, mori, mortuus, which means: to die.  So mori means: I died or I have died.

Thus the inscription should really be understood, as the skeleton chiding the wearer of the ring: "Remember, I died."