concert, consort

Concert or concert means a musical program or performance--
We have tickets for a concert, but we can't go.
He hasn't appeared in concert in years.

Concert may describe something related to a musical program or performance--
He is studying to be a concert pianist.
Thye have renovated the old concert hall.

Concert may also mean to plan or act together, especially in the phrase "in concert"--
She suspected that they had acted in concert, but she couldn't prove it.

Consort or consort means a companion or partner--
The queen and the prince consort will visit next week.

Consort may also mean to join or associate with--
She was tempted to consort with the enemy, so she left the party and went home.

Consort may mean a group of musicians, especially those playing antique instruments--
He plays the rebec in an early modern consort.

Now that you know that, you can say--
"A medieval consort is giving a concert this evening, and we hope you'll join us."
"They worked in concert to find anyone who might consort with the underworld."