I've said it before on other threads. Multiple meanings/derivations actually strengthen the reason for the word being used/retained. People take the inference that works for them. Multiple meanings means more people like it and use it.

Tarry - the person holding the drill was maybe not as skilled, all he had to do (all!) was stand there and hold the drill and wait for the hammer. May hap he was happy-go-lucky. Laid back.
Terrier - holding that drill needed tenacity. Digging. Irish.
tarrier - auger/drill.
tarrier/terrier - in an Irish accent might sound similar.

There! You have four legs on the table. It is now stable!