This is the 479th most frequent Dutch word.
hoewel
"Although" or "though."
Here, 'hoewel' introduces a clause expressing a contrast between the expectation (not going for a walk because of rain) and the action (going for a walk despite the rain).
Hoewel het buiten regent, gaat hij toch wandelen.
Although it rains outside, he still goes for a walk.
In this sentence, 'hoewel' shows concession, providing context for the unexpected decision to go to the beach despite the cold.
We gingen naar het strand, hoewel het wat koud was.
We went to the beach, although it was a bit cold.
Here, 'hoewel' introduces a surprising or contrasting factor (being tired) to his action (continuing to work).