duos, combo, threesome, combination, twosome, trios, meshing, melding, triumvirate, teaming, tandem, parings, coupling, foursome, partnership, blend, quaffer, swapping, duel, juxtaposition, simpatico, interplay, bedfellows, matchup, dovetailing, synergy, mignonette, bromance, setup, mix, digestif, complement, symbiosis, accompaniments, selections, rooming, burlesques, mingling, bookend, sublime, quartet, chemistry, choice, fivesome, comer, aperitif, opposites, collaboration, splitting, switching, kir royal, debutant, dalliance, duet, halves, tie, partnering, provencal, similarity, rapport, lineup, mash, grigio, starveling, permutation, pitting, debuts, teeing, saison, redcurrant, weizenbock, posset, newcomer, fusing, hyphenate, headliners, mate, cheeseboard, worldbeater, gelling, fruitiest, cheese souffle, flageolet, zabaglione, bulghur, pedigree, puckery, experiment, round, salad cream, synapsis, flirtation, buffo, arrangement, fetcher, twofer, sipper, pecking order, vidalia onion, swizzle, symphonist, homologous chromosomes, pairings, application, configuration, mating, placing, assignment, collocation, sighting, numbering, ordering, conjunction, instantiation, metric, naming, parameterization, parametrization, pattern, quote, sequence, coding, induction, interaction, propagation, substitution, labeling, bonding, correlation, diffusion, dipole, relaxation, retention, reversal, stimulation, synthesis, activation, binding, deformation, distribution

assortative mating, cross, crossbreeding, crossing, disassortative mating, hybridisation, hybridization, hybridizing, inbreeding, interbreeding, service, servicing

buddy system, conjugation, coupling, crossing over, crossover, match-up, matchup, mating, sexual union, synapsis, union

sex, sexual activity, sex activity