captaincupfulshippiesnephewspeppersriptiderupturezipping
One example of a four-letter word where the second and last letters are the same is "ball." In this word, the second letter 'a' is the same as the last letter 'l.' Another example is "hall," where the second letter 'a' is also the same as the last letter 'l.' These are known as palindromic words, where the word reads the same forwards and backwards.
Garbage
startle
startling
boxtops
Pepper
startle
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kayak and level
Exuded or exudes.
believed, believes, believer, relieved, relieves, reliever, helmeted