Co-national is a term used to describe someone who is a citizen of the same country as oneself. However, there are other words that can be used to express this same idea. One possible synonym is fellow countryman or countrywoman, which emphasizes the sense of shared identity and solidarity among members of the same nation. Another option is compatriot, which connotes a sense of loyalty and allegiance to one's homeland. Other words that can be used as synonyms for co-national include fellow citizen, national, and fellow patriot. All of these terms convey the idea of belonging to a common political community and sharing a collective identity based on nationality.