if your money is locked up, you have put it into a business,investment etc and cannot easily move it or use it
WORD CHOICE: WORD CHOICE: close, shut, lock, turn/switch offIn many contexts, the verbs close and shutcan be used in exactly the same way• Please close OR shut the gate. • The windows were all closed OR shut. • She closed OR shut her eyes.• The store closes OR shuts at 7.!! Use closefor a road, border, or airport• All the crossing points on the border have been closed (NOT shut).!! Before a noun, use closed• a closed door (NOT shut door)!! You cannot say 'close someone somewhere'. Use shut or lockto say that someone is put in a room or building and cannot get out• They shut her (NOT closed her) in her bedroom. • He was locked (NOT closed) in a cell.Use switch off or turn offwith electrical things• Will you turn off (NOT close) the TV? • I switched off (NOT closed) all the lights. ➔ See alsoclose
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.