pel
(
Elvish root) usually translated 'fence', but referring to any enclosing or surrounding structure such as a wall or even a range of mountains, or to an area enclosed by such a protective structure.  This element appears in 
Pelóri, the 
Mountains of Defence in 
Aman, whose name literally means 'fencing mountains'.  It also appears in the sense of a 'fenced region' or 'garth' in 
Pelargir ('garth of royal ships') and in a related form in 
Pelennor ('fenced land').  
Pel is also the root behind the word 
Ephel ('outer fence'), as in examples such as 
Ephel Dúath, the 
Mountains of Shadow that formed the outer defences of 
Mordor.
 
pelen
(
Elvish root) 'fenced', from 
pel- above, referring to a place surrounded by a protective wall as in 
Pelennor ('fenced land'), the lands of eastern 
Gondor surrounded by the 
Rammas Echor ('encircling wall').  The same element occurs in the name of 
Steward Pelendur, but there the meaning is less clear (perhaps 'servant of the protected').  
Pelen derives from a common root word 
pel that appears in various forms to describe protected or fenced locations, such as 
Pelargir ('fortified place of the royal ships'). Related is the word 
ephel (from 
et-pel, 'outer fence') giving rise to names such as 
Ephel Dúath (the 
Mountains of Shadow, but literally 'outer fence of shadows').
 
peregrin
(Latin) 'traveller', implying a traveller to distant lands, from the Latin 
peregrinus, originally meaning 'foreign, alien'.  Seen only in the name of 
Peregrin Took, one of the four 
Hobbits who joined the 
Fellowship of the Ring (and, probably by coincidence, were collectively known as the '
Travellers' on their return to the 
Shire).
 
phant
(
Sindarin) uncertain, but possibly a derivative of 
pant, 'full', 'complete', 'totality', this element appears in the name 
Araphant.  It is not clear whether that name is intended to have a translatable meaning, but it might be taken as 'king of all' (as an 
Heir of Isildur, 
Araphant had a claim to being 
King of all the Dúnedain, and indeed he took steps to reunite the crowns of the 
North- and 
South-kingdoms).  Note that the similar 
phanto in the name 
Turuphanto, while also somewhat obscure, does not seem to be related to 
phant in this sense.
 
pharaz
(
Adûnaic) apparently 'gold'; the 
Adûnaic language is not well documented, but the fact that 
Ar-Pharazôn of 
Númenor had a name regularly glossed as 'the 
Golden' points strongly toward this interpretation.  The final 
-ôn is apparently an adjectival suffix, turning 'gold' into 'golden', hence the full name 
Ar-Pharazôn would mean '
king golden'.  It is perhaps notable that the 
Elvish version of this name, 
Tar-Calion, uses a word for 'light' rather than 'gold', and so is not a direct translation (though it may possibly indicate that 
pharaz had a more specific meaning, perhaps implying 'shining gold' rather simply 'gold').
 
pimpernel
(English, from Old French) a small five-petaled flower commonly red or blue in colour.  The origins of the name are uncertain, but it is thought to derive ultimately from Latin 
piperinus, 'pepper-like', because of the shape of its fruits.  The flower gave its name to 
Pimpernel Took, one of the three elder sisters of 
Peregrin Took.
 
poros
(Source uncertain) the name of the river that separated the 
Gondorian province of 
Ithilien from 
Harondor or 
South Gondor.  The meaning of the name is uncertain; in a list of the rivers of 
Gondor, Tolkien marks 
Poros as 'boundary', which may be a translation of its name, or possibly a simple geographical description.  The name does not seem to meaningfully match any known 
Elvish roots, and so might conceivably represent a 
Mannish name for the river from pre-
Gondorian times.
 
porto
(Latin?) the names of members of the 
Baggins family appear to be largely nonsensical (and, for the most part, were probably meaningless even to the 
Hobbits themselves) but some of them can conceivably be understood as deriving from Latinate roots.  The name 
Porto is one of these, and might possibly come from from the Latin for 'carry', or possibly from its Italian descendant 
porto, which can mean 'carriage' or 'harbour'.  It might very well be that Tolkien did not intend the name of 
Porto Baggins to hold any meaning at all, but it is perhaps notable that his brother 
Ponto had a name comprehensible as a related word in Latin, specifically 
ponto meaning 'ferry' or 'pontoon' (in Italian, 
ponto means 'bridge').