Masculine nouns are the easiest to decline in Romanian, as there is very little irregularity. All masculine nouns (even those with irregular plurals, such as om (oameni) end in -i.
Masculine nouns are generally not difficult to identify. The usually end in consonants, -u, -e or -i. Because neuter nouns can also end in all of these, they can sometimes take a bit of work to differentiate, however, masculine and neuter nouns generally end in different consonants.
Masculine nouns ending in consonants will generally end in:
r (-or, -tor, -ar, -er)
n (-an, -ean, -ân) or
Neuter nouns ending in consonants will usually end in: