Yes, and the seat comes back either way. The place you do it depends on who you invited.
Before you cancel: three gentler fixes
A family invitation that has not been accepted sits under Waiting to join in your Circle, and the same spot offers three ways to rescue it without giving up the seat:
Copy link. Copies the invitation so you can paste it into your own text or email, for the relative whose inbox swallowed ours.
Send it again. A fresh email to the same address.
Fix the address. Correct a mistyped email and send to the right one. The seat stays held.
If you shared a link rather than sending an email, the last option reads Turn off this link instead of Cancel invitation.
A family member
Open your Circle.
Find them under Waiting to join.
Tap Cancel invitation, then confirm.
The link stops working immediately and the spot they were holding is free again, so you can invite somebody else straight away.
Nothing else changes, and nothing is lost. If you cancel by mistake, or they turn out to want in after all, just invite them again.
A professional caregiver
Go to Caregiver Access and find the seat marked Invitation Sent. The small red icon cancels it and returns the seat to open, so you can assign it to somebody else.
Who can cancel one
The older adult, or a Family Advocate. If you sent an invitation and cannot see the option, that is why, and anyone with it can cancel on your behalf.
If you would rather just wait
A family invitation expires on its own after 14 days, a caregiver one after 7, and then it cannot be used. Cancelling is only worth doing if you need the spot back sooner, or you would rather the link stopped working today.
If they have already joined
That is a different thing: see How do I remove someone from my Circle? Removing somebody takes away their seat, never their account.