Learner's definition of OBSTRUCT
to block (something, such as a pipe or street) so that things cannot move through easily
to slow or block the movement, progress, or action of (something or someone)
Several issues have obstructed [=hindered, impeded] efforts to bring peace to the region.
She was charged with obstructing police/investigators.
She was charged with obstructing justice by lying to investigators.
to be in front of (something)
to make (something) difficult to see