1650s, from Latin reticulatus "having a net-like pattern," from reticulum "little net," diminutive of rete "net," a word of uncertain origin, perhaps related to Lithuanian rėtis "sieve," or perhaps a loan-word from a non-IE language.
1787, back-formation from reticulated (1728), from reticulate (adj.). Related: Reticulating.
a reticulated highway system
the reticulate veins of a leaf