What does ecquī mean in Latin?

ecquī, a determiner, means “(Is there) any...?; whether (there is) any”.

How do you pronounce ecquī?

In classical Latin, [ɛkˈkʷiː.nãː]; in ecclesiastical (church) Latin, [ekˈkʷiː.nam].

determinerindeclinable portion with a relative/interrogative determiner

ecquī or ecquei or ecquis (feminine ecqua or ecquae, neuter ecquod)

Classical[ɛkˈkʷiː.nãː]Ecclesiastical[ekˈkʷiː.nam]

(Is there) any...?
Omnis est misera servitus; sed fuerit quaedam necessaria: ecquodnam principium ponetis libertatis capessendae?44 BCE – 43 BCE, Cicero, Philippicae 10.19
whether (there is) any
Nam mihi, Brute, in te intuenti crebro in mentem venit vereri, ecquodnam curriculum aliquando sit habitura tua et natura admirabilis et exquisita doctrina et singularis industria.46 BCE, Cicero, Brutus 22.3

singular
form	masculine	feminine	neuter
nominative	ecquīnam ecqueinam, ecquisnam	ecquaenam	ecquodnam
dative	eccuinam ecquoinam, ecquoī, quoeinam, ecquoiī, quoieinam	eccuinam ecquoinam, ecquoī, quoeinam, ecquoiī, quoieinam	eccuinam ecquoinam, ecquoī, quoeinam, ecquoiī, quoieinam
accusative	ecquemnam	ecquamnam	ecquodnam
ablative	ecquōnam ecquīnam	ecquānam ecquīnam	ecquōnam ecquīnam

plural
form	masculine	feminine	neuter
nominative	ecquīnam ecqueinam	ecquaenam	ecquaenam
accusative	ecquōsnam	ecquāsnam	ecquaenam

From ecquī + -nam. See also ec-, ecquis and ecquisnam.