This is the 5106th most frequent Portuguese word.
mosquitos
Mosquitos: Small flying insects that feed on blood.
Here, "mosquitos" refers to specific insects as the subject of the sentence.
Os mosquitos são insetos que vivem em áreas úmidas.
Mosquitos are insects that live in humid areas.
In this sentence, "mosquitos" is used as the subject implying their actions of entering a room.
Durante a noite, os mosquitos invadiram o quarto.
During the night, mosquitos invaded the room.
Here, "mosquitos" indicates the possessive context, referring to their bites and effects thereof.