Wiktionary
fettler
n. 1 A person who maintains railway lines. 2 Someone whose job is to sand and grind small imperfections from metal and ceramic castings. 3 (context by extension English) Someone who fiddles or tinkers with things. 4 (context slang UK Lancashire English) A friend or mate
Usage examples of "fettler".
By the time he’d dealt with that, Fettler was assisting his brother back into his coat.
Lastly, Fettler pinned the silver star of the Order of the Bath to his left breast, the gold cross in the middle being the only color about him.
Clearly Fettler had told him of her visit to his rooms and he’d guessed the reason.