Thoroughly

adv.capable, thoughtfulprofessional

What it means

In a careful way that covers every important part.

Reach for it when describing work completed with both detail and full scope

The engineer thoroughly checked the supports before reopening the footbridge.

playful
from top to bottom
when complete practical inspection suits an informal voice
not when The idiom is too casual and spatial for formal analytical work.
everyday
carefully
when avoiding mistakes is the main aim
not when Carefully does not promise that the full scope was covered.
everyday
completely
when total extent matters more than care
not when Completely can describe a rushed action that reaches every part without examining any part well.
professional
meticulously
when fine detail and precision dominate
not when Meticulously can imply painstaking detail within a narrow slice rather than complete coverage.
professional
systematically
when an ordered method prevents omissions
not when A systematic process can still use shallow checks.
formal
comprehensively
when all relevant topics or categories are included
not when Comprehensively says less about close examination of each item.
formal
exhaustively
when virtually every possibility was investigated
not when Exhaustively overclaims work that covered everything material but not every conceivable case.

check thoroughly
Inspectors check thoroughly before signing the occupancy certificate.
thoroughly tested
The alarm was thoroughly tested in daylight and blackout conditions.
thoroughly understand
A reviewer must thoroughly understand the exception before approving it.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.