chantajear
blackmail
chant
to sing repeatedly
+
age
a period of time
+
-ar
verb suffix
Chantajear means to blackmail. While not etymologically correct, it can be remembered as chant0 + age1 + -ar2, like 'chanting about someone's age' to pressure them.
verb
  1. blackmail
    To blackmail or extort someone
    El criminal intentó chantajear al político con fotos comprometedoras. // The criminal tried to blackmail the politician with compromising photos.