Echar (Spanish for "to throw," particularly in the metaphoric sense such as, "to throw out") comes from the Latin Iactare, meaning "to throw". From the same root, we get the English jet — a jet plane throws itself at an incredible speed!
But the words look nothing alike? How is that?
Two patterns, we must remember. Firstly, the ct- sound in Latin became a ch- in Spanish. Hence the ct- in ictare now looks like the ch- in echar. Secondly, Latin had no "j" and the initial "i" in Latin often became a "j" in English. Hence, the "j" in jet!