featherweight
Palmately compound leaves have multiple leaflets that radiate from a single point, like fingers on a hand (e.g. poison ivy). Pinnately compound leaves have leaflets arranged along a central stalk, resembling a feather (e.g. rose leaves). Bipinnately compound leaves have leaflets arranged in multiple levels, resembling a feather within a feather (e.g. acacia leaves).
Bluebird.
If you are referring the "feather bedding" (two words) it refers to bedding products that are filled with feathers or down from [typically] a goose. For example, a feather pillow, a feather comforter, a feather blanket, a feather mattress topper.
compound words
Yes, into and today are compound words.
Compound words that have when in them are whence, whenever, and whensoever.
No, if they are separate words they are not compound.
The group of words, "a feather in your cap" is not a sentence, it contains no verb.There is one pronoun in the phrase "a feather in your cap", the possessive adjective your.
compound words written as two
Some compound words that have "oil" in them are: oilcloth, oilrig, oilcan, oilskin.
A feather is an organic item and therefore contains carbon
Compound words can be made with almost any two words.