Denshi Jisho — Online Japanese dictionary

れい instar
Noun 
よわい (one's) age
Common word, Noun 
弱い よわい weak; frail; delicate; tender; unskilled; weak (wine)
Common word, Adjective 
弱い者 よわいもの weak person; the weak
Noun 
弱い経済 よわいけいざい weak economy
Noun 
弱い相互作用 よわいそうごさよう weak interaction
Noun, Physics term 

You can also

Look up kanji details for 齢 よわい.

Try a Yahoo Jisho search for 齢 よわい .
Try a Goo Jisho search for 齢 よわい .
Try a Google search for 齢 よわい .