BLUNDERER

bungler, blunderer, fumbler, bumbler, stumbler, sad sack, botcher, butcher, fuckup

(noun) someone who makes mistakes because of incompetence

Source: WordNet® 3.1

Etymology

Noun

blunderer (plural blunderers)

One who blunders.

Synonyms

• See also unskilled person

Source: Wiktionary

Blun"der*er, n.

Definition: One who is apt to blunder.

Source: Webster’s Unabridged Dictionary 1913 Edition