Investigate (5)

'investigate' is the definition.
(I know that investigate is a more specific form of the action probe)
This is all the clue.
(Other definitions for probe that I've seen before include "Spacecraft; investigation" , "Poke into" , "Question or examine thoroughly" , "sound" , "Inquiry" .)
'investigate' is the definition.
(I know that investigate is a more specific form of the action examine)
This is all the clue.
(Other definitions for examine that I've seen before include "Question (a witness)" , "Test or study carefully" , "Inspect carefully" , "Inspect, peruse closely" , "Inspect , test" .)
'investigate' is the definition.
(I know that explore is a more specific form of the action investigate)
This is all the clue.
(Other definitions for explore that I've seen before include "Travel through region to learn about it" , "Investigate in detail" , "Travel in search of discovery" , "Examine or investigate, new country or possibilities" , "Examine by touch" .)
(Other definitions for checkup that I've seen before include "Precautionary or routine visit to G.P." , "Quick dental visit" , "An occasional precautionary medical examination" .)
'investigate' is the definition.
(I know that investigate can be written as look into)
This is all the clue.
(Other definitions for look into that I've seen before include "probe" , "Enquire about, investigate" , "Try to discover the facts" , "Investigate - visually?" , "Study" .)