In cooking, to coddle food is to heat it in water kept just below the boiling point. In the past, recipes called for coddling fruit, but in recent times the term is usually only applied to coddled eggs. The process is either done in a regular pan or pot, or through the use of a special device such as an "egg coddler" (originally known as a pipkin).
The word coddle evolved from the name of a warm drink, "caudle", and ultimately deriving from the Latin word for warm drink, calidium.
Look up coddle in Wiktionary, the free dictionary.
Comparing the coddling cooking technique to boiling when it comes to whole eggs, the process of coddling takes a longer amount of time due to the use of a lower cooking temperature, but it produces a more tender egg.