Meaning of head-to-head

(adj) involving two persons; intimately private; "a tete-a-tete supper"; "a head-to-head conversation"

inconclusive as to outcome; close or just even in a race or comparison or competition; "as they approached the finish line they were neck and neck"; "the election was a nip and tuck affair"

(adv) even or close in a race or competition or comparison; "the horses ran neck and neck"; "he won nip and tuck"