There is a word used specifically for lying relaxed in a bed or someplace comfortable, stretched out and not wanting to move from that position. Problem is, I can't remember what the word is called, just knows it starts with the letter "p". Help a brotha out (:
Have a lie-in is an expression that conveys the meaning you are referring to:
A prolonged stay in one's bed in the morning. Often hyphenated. Primarily heard in US.
- Your mum's having a lie in this morning, so we need to be extra quiet downstairs. I love having a long lie-in on Sundays.
(The Free Dictionary)