My Dad, Age 95, Is Having Problems Expressing His Thoughts.

My dad, age 95, is having problems expressing his thoughts. He knows what he’s trying to say, but can’t think of the word for it. This starte last night and has continued this morning. He has no drooping of facial muscles, had him squeeze my hands and he had equal strength in his hands, checked his feet up and down. Both were equal force. Eyes are clear and track well. Pupils are equal and reactive. Is this just age related, or is his language difficulty a symptom of something more serious? Thank you for whatever advice you can give me.