‖ Acaridæ,n.pl.Zool.|əˈkærɪdiː| [mod.L., f. Acar-us + -idæ.] A family of small Arachnida, breathing by pores like insects; comprising mites and ticks. (For the sing.Acaridan is used.) 1847Carpenter Zool. II. §766 The Acaridae are very widely, in fact universally, distributed.