Meaning of つかみどころがない on a person

Question

I have seen the literal translation of the phrase 「つかみどころがない」, somewhere along the lines of being either slippery, vague or elusive. I encountered this phrase

立花｛たちばな｝さんつかみどころないんだよなぁ…

I cannot seem to extend the translation into this sentence. The context suggests that it means the person is kind of hard to talk to (awkward silence), but maybe that's irrelevant for this sentence.

UPDATE: I wrote "literal" translation, but really it's not literal and it's simply the definition given by dictionaries. Apologies for the confusion.

Answer 1

have seen the literal translation of the phrase 「つかみどころがない」, somewhere along the lines of being either slippery, vague or elusive.

I do not see how those can be called the "literal" translations.

「つかみどころがない」 comes from the phrase 「掴{つか}むところがない」. 「掴む」 means to "grab", "catch", "grasp", "take hold of", etc.

「つかみどころがない」, therefore, literally means "there is no part to grasp".

When that is said about a person, it means that you have no idea what s/he really has in mind and/or there is a mystery about him/her, which is why the dictionaries would give the definitions of "vague", "slippery", "elusive", etc.

Answer 2

The phrase つかみどころがない has its own entry in EDICT where it is listed as "vague; fuzzy; elusive; slippery". That's where those translations you are seeing coming from. Nearly every J->E dictionary site or application out there is cribbed from EDICT.

The Goo dictionary has an entry for 掴みどころ, which has 掴みどころない人 as an example:

つかむ部分。また、そのものの本質や真意を押さえる手がかりとなる点。とらえどころ。つかまえどころ。「話の掴み所をさがす」「掴み所のない人」

Literally translating, the tsukamidokoro is the point in a material which provides the clue to pinning down its true essence or meaning.　In other words, it's something we can latch onto for understanding.

My old 1993-dated 国語辞典 from 講談社 has it briefly as 「ここぞという、たいせつな点。手がかり。」as a sub-entry under 掴み.

A 掴み所のがない人 is someone whose actions and words reveal nothing we can connect with for an understanding.