We don't have synonyms for pentel yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are pencel, puntel and mentel.
(n) :
(inorganic chemistry, rare) A pnictogen or element from group 15 of the periodic table, which includes elements nitrogen, phosphorus, arsenic, antimony and bismuth.
(n) :
(inorganic chemistry, rare) A pnictogen or element from group 15 of the periodic table, which includes elements nitrogen, phosphorus, arsenic, antimony and bismuth.