avaient
had (possessed)
had (characteristic or state)
Ils avaient beaucoup d'amis à l'époque.
They had many friends back then.
had (auxiliary used to form the pluperfect/plus-que-parfait)
Elles avaient déjà fini leur travail.
They had already finished their work.
Notes
GENERAL INFO
Avaient is the imperfect tense, third-person plural form of the verb *avoir* (to have). It means "they had" or "you all had" (formal/plural).
USAGE
It describes past states, habitual actions, or ongoing conditions. For example: "Ils avaient faim." (They were hungry / They had hunger.) "Elles avaient l'habitude de se promener." (They used to walk.)
TRAPS
Do not confuse it with the *passé simple* form "eurent" (they had - literary past) or with "avaient eu" (they had had - pluperfect). It's also an auxiliary verb in the pluperfect: "Elles avaient mangé." (They had eaten.)
