κατέφαγεν [7 verses](3rd sg aor ind act) "Devoured" is from katesthio, which means "to eat up" and "to devour." Literally, it means "eat down" with the prefix kata- meaning down." It is a term applied to animals of prey. It also means "to corrode" or "to be gnawed."  -  "Devoured" is from a verb that means "to eat up," "eat down," and "to devour."   It is a term applied to animals eating their prey. It also means "to corrode" or "to be gnawed." 

κατεξουσιάζουσιν [2 verses](verb 3rd pl pres ind act) "Exercise authority" is katexousiazo, which gets translated "to have power," "to exercise power," and "to be the master of a body." From kata, which means "downwards," "down from," "down into," and "against." And a verb from of exousia which means "control," "the power of choice," "permission," "the power of authority," "the right of privilege," "abundance of means," and "abuse of power."

καθελῶ [1 verse](verb 1st sg fut ind act) "Pull down" is kathaireo, which means "take down", "put down", "put down by force", "destroy",  "put down", "reduce,  raze to the ground", "demolish", "cancel", "rescind", "overpower", and  "seize". - -The unique Greek word is translated as "pull down" and means "take down", "put down", "put down by force", "destroy",  "put down", "reduce,  raze to the ground", "demolish", "cancel", "rescind", "overpower", and  "seize".

καθαίρει [1 verse]  (3rd sg pres ind act) "Purges" is kathairo, which means "to cleanse," "to purify" [in a religious sense], "to purge," "to evacuate," "to prune" [a tree], "to winnow," [grain], and "to wash off." - "Purges" is a Greek verb means "to cleanse," "to purify" [in a religious sense], "to purge," "to evacuate," "to prune" [a tree], "to winnow," [grain], and "to wash off."

καθαρισμοῦ {καθαρμός  [1 verse]( noun sg masc gen ) "Cleansing" is katharismos, is a form of katharmos, which means " cleansing," and "purification." - "Cleansing" is from a Greek noun in a form that is only used by Jesus once.  It is a different form of a Greek word that means "cleansing," and "purification."

καθαρίζονται [12 verses](verb 3rd pl pres ind mp) "Be clean" is katharizo, which means "to clean," "to clear the ground of weeds," "prune away," "to remove dirt," "to purify,"and "to remove impurities." It is also used to describe the removal of the inedible parts from grain (winnowing), clearing weeds from a field, pruning a plant and so on.-- The Greek word translated as "be clean," means to remove dirt. It is used for a lot of specific types of "cleaning" including cleansing a person of leprosy but it also has a general meaning of "purifying" anything.

καθαρόν. [5 verses](adj sg masc acc) "Clean" is katharos, which means "physically clean," "spotless," "clear," "pure (water)," "clear of objects," "free of contamination," "clear of debt," "genuine," "pure of birth," "without blemish," and "sound." -- The Greek word translated as "clean" means "physically clean," "spotless," "free of contamination," "clear of debt," "genuine," "pure of birth," "without blemish," and "sound."

καθέδρας [4 verses](noun pl fem acc)  "Seat" is kathedra, which means "a chair," "a seat" "a sitting position," "the sitting part," "the posterior," "sitting idle," "inaction," "the chair [of a teacher]," "a session," and "a throne," is used to denote a position of power. From the Greek kata("down") hedraios ("to settle") .

καθηγηταί, [1 verse](noun pl masc dat) "Masters" is kathêgêtês, which means "guide" and "teacher" and "professor."  - "Master" here is the same root as "masters" above.

καθημένοις [13 verses](part pl perf mid masc dat) "Sitting" is kathemai, which means "to sit," "to be seated," "to sit still," "to sit quiet," "to reside," and "to be placed."  - "Sitting" is a Greek verb that means to "be seated," "sit," especially of courts, councils, assemblies, etc.  The sense of being put in a position of authority as we would say "chair." It also means to "sit still" or "sit idle."