Could you please tell me the difference between especially and particularly?

You need to give a sample sentence for us to discuss.

The meaning can be gleaned from how it is used in the sentence.

I don't think there is a difference. They are pretty much interchangeable.

It's very tenuous to say the least, but the way I see it,
particularly tends to look at one specific 'item' without really emphasizing the relation to the rest of the items it was selected from, where especially does seem to relate to the other 'items' the one 'item' was picked from.

But that is stretching it a bit. Even if my hunch is correct, the difference is quite miniscule and McTag is completely right when he says the words can pretty much be used interchangeably.

I'd say that there is a slight difference in register with particularly being a wee bit more formal. What I mean by this is that, [I think and I may be wrong] especially would be found more in speech and less in, say, academic writing.

If you are near a big library, they may have

The Longman Language Activator

You can see what it looks like at this link:

http://www.amazon.com/s/ref=nb_ss_gw?url=search-alias%3Dstripbooks&field-keywords=Longman+Language&x=0&y=0

If there are any differences, it likely will note them.

We don't 'look up' dictionaries, Majidkh, we look up [something] in dictionaries/encyclopedias/etc.

looking them up in different dictionaries didn't help me.

It was an especially warm day.

It was a particularly warm day.

There is certainly a difference in meaning between "special" and "particular".

But not, in the way we use them, between "especially" and "particularly", in my opinion.

I think that "especially" makes a thought or experience stronger. It could be a positive or a negative.
"My ex-husband was especially sweet when he was trying to get me to agree to sharing the house. . .; he was quite (especially) nasty when he suggested that I didn't care for the poodle properly."

And "paricularly" singles out and highlights an experience or occasion. "He was particularly nasty when he said that I didn't trim her toenails properly!"

particular mean one chosen out of many. it would be like no other.

especially means a degree of being special, different, unusual.

As an adjective yes, 'particular' does mean that, SF, but with 'ly', as an adverb is it not an intensifier?