Is there a well-known term for the synonym or near-synonym "telescoping" words?

I think kangaroo word is the closest term for this.

A playful term for a word that carries within it a synonym of itself--such as regulate (rule), indolent (idle), and encourage (urge).

It's generally believed that the synonym (called a joey) should be the same part of speech as the kangaroo word and its letters should appear in order.

_{http://grammar.about.com/od/il/g/kangaroowordterm.htm}

There are also twin kangaroos and anti-kangaroo words.

Twin kangaroos are kangaroo words containing two joey words (for example: container features both tin and can). In contrast, an anti-kangaroo word is a word that contains its antonym; for example: covert carries overt, animosity carries amity.

[Wikipedia]