gneiss / nice 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. 👇
gneiss: (noun) a laminated metamorphic rock similar to granite.
nice: (noun) a city in southeastern France on the Mediterranean; the leading resort on the French Riviera. (adjective) pleasant or pleasing or agreeable in nature or appearance; - George Meredith. (adjective) done with delicacy and skill.
gneiss: n·AY·s
nice: n·AY·s
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)