Dic: essentially

• It's been believed for centuries that great writers, composers and scientists are essentially quite different from ordinary people...
• Essentially, vines and grapes need water, heat and light.
• That, essentially, is the difference between them.
• Essentially, NATO was giving Saddam an ultimatum.

1. [ADV] ADV with cl/group △You use essentially to emphasize a quality that someone or something has, and to say that it is their most important or basic quality. (FORMAL) (= fundamentally)
1. used for emphasizing what is the most important aspect of something or fact about something:

* * *

• His analysis of urban use of agricultural land has been proved essentially correct...
• Essentially, the West has only two options... 
• The list is essentially complete.

2. [ADV] ADV with cl/group, ADV with v △You use essentially to indicate that what you are saying is mainly true, although some parts of it are wrong or more complicated than has been stated. (FORMAL)
2. used for saying that something is mostly true, but not completely true:

... COBUILD, MacMillian