Ok, I'm going to get as detailed as possible since I think that's what you're looking for. This is going to be a little hard to explain, since I assume most people don't have Japanese characters installed on their computer. I'll put them in, but they'll look like random boxes if you don't have the script.
The character 忍 by itself is read as "nin", which means to bear/endure/conceal/hide/spy. I couldn't think of a good example myself, but my favorite online dictionary suggested this: 忍を行じてのみ、よく怨みを解くことを得る。 (By love alone is enmity allayed)
nin wo kojite nomi, yoku urami wo hodoku koto wo uru. To be honest, if "bear/endure/conceal" is what you want, I would say that's fine for a tattoo.
Thing is, this character by itself is not often seen...by itself. One of the common misconceptions about Japanese characters is that they always work well as 'stand-alone' characters and can be combined at will. Most do have some sort of individual reading, but are more commonly found in combinations either with other kanji or with characters from the Japanese hiragana alphabet. Most of the funny kanji tattoos you'll see non-japanese sporting are people who combine individual character meanings to mean something they think is cool, but it ends up backfiring. My favorite example is combining 天 ten "Heaven" 気 ki "Spirit" and 人 jin "Person", which sounds cool if Heavenly Spiritual Being was actually what it meant. But when you combine "Heaven" and "Spirit" 天気 tenki it becomes "Weather", so that tattoo looks more like "Weather Person".
The character you have chosen is commonly found paired with a character which can be read as "mono" 者 (a humble form of person) or also read as "sha". When combined with the 忍 nin character you have chosen, it becomes "Ninja" 忍者. Combine it with the character 術 "jutsu" and it becomes ninjutsu or the "art of invisibility" or ninja art.
Or when you combine it with the hirgana letter "bi" び, it becomes Shinobi 忍び which is basically the same as ninja. (But notice it's no longer read as "nin" but has become "shino". Which is why learning Japanese can sometimes drive you nuts.) The "shino" version appears in the town name 忍野 "Oshino" which is a tiny tourist town I have visited. If I had to guess, the meaning of the town's name is probably "hidden field" which would be a pretty accurate description.
If you are not confused by all this and still like the character, I say go for it.
This post has been edited by Shinrei: 29 February 2012 - 01:13 PM
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