How and where is the word "Dar" used in a sentence, as well as the word "Darbh" (is Darbh the past tense of this)?

Dar le daoine airithe, níl faic ach an liathróid mór i gCiarraí ach tá an fhirinne ag muintir Leic Snámha.

(Dar le = according to)

Tá brón orm - rinne mé dearmad ar "darbh".

When you put the copula (is) together with de (of), you get "dar". I don't know if this is the same dar as the one I mentioned above (help!). When put before a vowel, this becomes "darbh". The most common use I am aware of is in connection with names - tá cara agam darbh ainm Séamas - I have a friend called Séamas - or (literally) I have a friend who is of the name Séamas.

Casadh orm le fear darb ainm [name here]
I met a man called [name here]

Casadh orm (gan an "le")

fear dar sloinne X = a man whose surname is X
fear dar shloinne X = a man whose surname was X
fear darb ainm X = a man whose name is X
fear darbh ainm X = a man whose name was X

Lars

go raibh maith agat, a Lars.

Presumably darb is present tense and darbh past these.

Also gach..de

every language he learned: gach teanga dar fholaim sé

but what does "darb" mean?

FGB has this:

Dar, compound of prep. do or de and indirect rel form ar of copula. (Lenites in past tense; becomes darb before vowel in pres. tense, darbh before vowel or fh followed by vowel in past tense. 1. For whom (is). an té dar dual an mi-ádh., he who is unfortunate by nature. an fear dar mhiste é, the man to whom it mattered.

Bean darb ainm Deirdre, a woman whose name is Deirdre.

Bean darbh ainm Deirdre, a woman whose name was Deirdre.

(Message edited by bodhrán on November 12, 2009)