serge / surge are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
serge: (noun) a twilled woolen fabric.
surge: (noun) a sudden or abrupt strong increase. (verb) see one's performance improve.
serge: s·ER·jh
surge: s·ER·jh
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)