熟語【じゅくご】 are basically kanji compounds that use two kanji's 音読み and creates a word out of it.
One common example of 熟語 is the word 今度【こんど】. This consists of the 音読み of the kanji 今 (English meaning: now) and the kanji 度 (English meaning: occurence/time). Put these two kanji together, and you get "this time/next time".
熟語 only use the 音読み of a kanji and never a 訓読み of it.
Here are some more prime examples of 熟語:
>>>勉＝ベン (exerting [efforts])
And some rather difficult 熟語:
>>>再＝サイ (again/second time)
I could go on forever with this ordeal, but hopefully, this is enough for you to understand the concept of 熟語.
ROMAJI version to come if enough people request it.
Wow, it's been a while since I updated my profile...since '08, actually. :o