ἁρπαγῆς [2 verses](noun sg fem gen)"Extortion" is harpage, which means "seizure," "robbery," "rape," "the thing seized," "booty," "prey," and "greediness,"

ἅρπαγες. [2 verses](noun pl masc nom ) "Ravening" is harpax, which means "robbing", "rapacious," "rapine", "robber", "peculator", "a type of wolf", "grappling-iron," and "meat hook."  - Surprisingly, the word translated as "ravening" also means a "grappling hook" and "a type of wolf," but its primary meaning is robbing and other forms of theft.

ἁρπάζουσιν [6 verses](3rd pl pres ind act) "Take...by force" is from the Greek harpazô, which means to "snatch away," "seize hastily, " "snatch up," "overpower, " "overmaster," "grasp with the senses," "plunder," "carry off," and "be a robber."  - "Catch" is a verb that means "to snatch away," "to carry off," "to overpower," and "to plunder." It is in the present tense. This is not an uncommon word for Christ to use. Everywhere else it is translated as "snatch," "seize" or "catch." 

ἑαυτῆς [75 verses](adj sg fem gen) "Himself" is heautou, is a reflexive pronoun that means "himself," "herself," "itself" "themselves," and "ourselves." It is not the common pronoun meaning simply "he," "she," "them," etc. In the genitive form, it has the sense of "his own." -- "Himself" is a special reflexive pronoun that means "himself," "herself," and so on. " When used in the possessive, it has the sense of "his own."

ἡδονῶν [1 verse](noun pl fem gen) "Pleasures" are from hedone, which means "enjoyment," "pleasure," "a pleasure," in plural, "desires after pleasure," and "pleasant lusts."  - "Pleasures" are from a Greek word that means "enjoyment," "pleasure," "a pleasure," in plural, "desires after pleasure," and "pleasant lusts." It is the source word from our word "hedonism."