- to form a mental image of (something incapable of being viewed or not at that moment visible) 
WordReference Random House Learner's Dictionary of American English © 2025
vis•u•al•ize /ˈvɪʒuəˌlaɪz/USA pronunciation  
v. [~ + object], -ized, -iz•ing. 
vis•u•al•iz•er, n. [countable]See -vis-.
WordReference Random House Unabridged Dictionary of American English © 2025- to form a mental image of:tried to visualize future events.
vis•u•al•iz•er, n. [countable]See -vis-.
vis•u•al•ize 
(vizh′o̅o̅ ə līz′),USA pronunciation v., -ized, -iz•ing. 
v.i.
v.t.
 vis′u•al•iz′a•ble, adj. 
vis′u•al•i•za′tion, n.
vis′u•al•iz′er, vis′u•al•ist, n.
v.i.
- to recall or form mental images or pictures.
v.t.
- to make visual or visible.
- to form a mental image of.
- to make perceptible to the mind or imagination.
- visual + -ize 1810–20
vis′u•al•i•za′tion, n.
vis′u•al•iz′er, vis′u•al•ist, n.
Collins Concise English Dictionary © HarperCollins Publishers::
'visualize' also found in these entries (note: many are not synonyms or translations):