The Spanish word 'osito' meaning 'little bear' is formed from two parts: the noun 'oso' (meaning 'bear') and the diminutive suffix '-ito'. The base word 'oso' comes from Latin 'ursus' meaning 'bear'. The diminutive suffix '-ito' is a very common Spanish ending that makes words smaller or more endearing, similar to adding '-y' or 'little' in English.

The most obvious related Spanish word is 'oso' meaning 'bear', which is the base word from which 'osito' is derived. While 'oso' refers to any bear, 'osito' specifically means a small bear, baby bear, or teddy bear, making it a more affectionate term.

While not immediately obvious, the English word 'ursine' (meaning 'relating to or characteristic of bears') comes from the same Latin root 'ursus'. This connection can also be seen in the scientific name for bears, 'Ursidae', and in the constellation name 'Ursa Major' (Great Bear) and 'Ursa Minor' (Little Bear).