cinque / sank 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. 👇
cinque: NA
sank: (verb) fall or descend to a lower place or level. (verb) cause to sink. (verb) pass into a specified state or condition. (verb) go under,. (verb) descend into or as if into some soft substance or place.
cinque: s·IH·ng·k
sank: s·AE·ng·k
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)