dream

1 dream /ˈdriːm/ noun
plural dreams
1 dream
/ˈdriːm/
noun
plural dreams
Britannica Dictionary definition of DREAM
1 
[count] : a series of thoughts, visions, or feelings that happen during sleep
— see also wet dream
2 
[count] : an idea or vision that is created in your imagination and that is not real
3 
a  [count] : something that you have wanted very much to do, be, or have for a long time
— see also american dream, pipe dream
b  [singular] : someone or something that has the qualities that a person wants most
— usually used before another noun
— see also dream team
4 
[singular] informal : something that is beautiful, excellent, or pleasing
5 
[singular] : a state or condition in which you are not thinking about or aware of the real things that are around you

in your dreams

informal
— used to say that you do not think something that another person wants or expects will ever happen
2 dream /ˈdriːm/ verb
dreams; dreamed /ˈdrɛmt/ /ˈdriːmd/ or dreamt /ˈdrɛmt/ ; dreaming
2 dream
/ˈdriːm/
verb
dreams; dreamed /ˈdrɛmt/ /ˈdriːmd/ or dreamt /ˈdrɛmt/ ; dreaming
Britannica Dictionary definition of DREAM
1 
: to have visions and thoughts in your sleep : to have a dream while you are sleeping
[no object]
— often + of or about
[+ object]
2 
: to think about something that you wish would happen or something that you want to do or be
[no object]
— often + of
[+ object]

dream on

informal
— used to say that you do not think something that another person wants or expects will ever happen

dream up

[phrasal verb]
dream up (something) also dream (something) up
: to think of or invent (something) in your mind

never/not dream of

— used to say that you would never do something or think of doing something