Yes, 'a dit' means 'said'. The auxiliary 'a' means '[he/she/it] has'. The past participle 'dit' means 'said'. Together, they're pronounced ah dee'.
"J'ai dit" in French translates to "I said" in English.
Bien dit in French means "well said" in English.
The French word for "said" is "dit."
Le Roi l'a dit means "the king has spoken." Literally, "it has been said".
DIT
The French word dit ("said," "told") between two names indicates that it is a nickname or an unofficial name.
I said is " j'ai dit " in French.
Comment dit-on en français? in French is "How does one say in French?" in English.
"How do you say...?" is an English equivalent of the incomplete French phrase Comment dit-on...? The question translates literally as "How does one say...?" in English. The pronunciation will be "kuh-maw dee-to" in French.
Dit.
"dit".
Dit means 'says' in English. C'est ce qu'elle dit > that's what she says.