solid | inanimate | everyday, household
Her paintings are of ordinary everyday objects.

main, primary, principal | sole
My sole object is to get to the bottom of this mystery.

lesson
The plans are an object lesson in how to ruin a city centre.

the object of the exercise
The object of the exercise is to score as many points as possible.

strenuously, strongly, vehemently

can/could hardly
It was your own idea in the first place, so you can hardly object now.

be entitled to, have a/the right to

to
a petition objecting to the scheme

object on the grounds that …
I objected on the grounds that it was unkind to the animals.