Eques (pl.equessi) is Quenyan for 'saying', 'dictum', 'quotation'.
I Equessi Rúmilo are the ancient saga of Tirion that was handed down by tradition of mouth.
Eques is also the verb equë (that was used mostly just before an independent pronoun or after 'that'-conjuction) having an affix added to it, making a meaning said he, said someone. This structure was usually used in reporting a dialogue.
Source: HoME XI, 392; 397-398; 415.