Subtract a letter...

[Rudi]

What nine letter word in the English language is still a valid word when letters are removed one by one down to the final letter?

[HansV]

Spoiler

mailbox
A mailbox containing nine letters is still a mailbox if you remove the letters one by one.

[HansV]

I don't know the 'real' solution, but I guess you'd have to start from the other end.

Spoiler

The only valid one-letter words are "a" and "I" (if you don't count "U" for "you").
From "a" one could go to "at", "rat", "rate", "rater", "grater", "greater", for example, but then I get stuck.
From "I" one could form "in", "sin", "sing", "sting", "string", "staring", "starling", "startling" - that's it! A startling solution!

[Claude]

I've got to go and sleep now, so, please email me the answer ASAP because I need some rest, ta

[HansV]

There is a possible solution in my previous reply.

[Claude]

Hint to Claude: refresh screen before replying.

[Rudi]

You got it Hans :)

Spoiler

There are at least four words that meet that criteria: startling, stringier, sparkling, and splitting.

Example :

STARTLING
starting
staring
string
sting
sing
sin
in
I

Other Words
If a plural "s" is allowed, these words are also nine letters : cleansers, splatters, drownings, wrappings, starvings and trappings. Similarly, the word discusses, and the past tense forms replanted and restarted (end with A). Also scrapping and strapping (if you allow pi as an English word).

*These two words share part of the sequence above:
stringier - stingier - stinger - singer - singe - sine- sin in - I
splitting - spitting - sitting - siting - sting - sing - sin - in - I